The following is an edited transcript of an in-house discussion that took place among the Baseball Prospectus staff when one of our number solicited examples of unsupportable baseball arguments for an upcoming article. After Kevin proposed "Anyone can close," the thread took off in a new direction.

Kevin Goldstein: "Anyone can close." While overstated, there is a human element to the game. These are not robots, nor are they strat cards you can just flop into any role or situation and expect the same results.

Gary HuckabayYes, and has anyone ever claimed otherwise?

Jonathan BernhardtIf only they were; then I could just wait for the balance patch that would make Baltimore playable.

Rany JazayerliWait, what?

I used to think that there were pitchers who were capable of being competent relievers, but who were incapable of handling the ninth inning. And then Kyle Farnsworth made me look like a fool this season. It's possible there are otherwise fine relievers who can't handle the stress of the closer's job, but I'll need some proof—or at least a list of their names—before I'll believe it again.

JB: The only pitcher I've ever heard of or seen who actually seemed to be affected by the Weight of the Closer's Mantle was one LaTroy Hawkins.

John PerrottoWhen I was first covering the Pirates, I saw Jeff Robinson go from being perhaps the best set-up man in the National League in 1988 to completely melting down in 1989 when he was forced into the closer's role when Jim Gott blew out his elbow on Opening Day. There are some pitchers who can't handle closing. I've seen it happen with my own eyes and been around them. Not everyone can close, even though it seems like they should.

JBWell, it makes sense that there's a feedback loop of some kind; if you're convinced closing is extremely important, and everyone around you is convinced it's extremely important, and you're praised or cursed as if your results in that role are extremely important, then psychologically speaking, it really doesn't matter if it's actually important at all.

KG: Also, Matt Thornton sends his warmest regards.

David Pease: Maybe there are people that can't handle the pressure, and maybe the average major-league reliever can handle the pressure.

Bradley AnkromI don't think we're anywhere close to being able to analyze players psychologically. I know some clubs have made advances in this area, but fans/analysts attempting to draw conclusions from limited circumstantial evidence seems foolish.

Rebecca Glass: The hullabaloo over Zack Greinke comes to mind. And yes, I'm replying just so I can use the word "hullabaloo."

Ben Lindbergh: The case for Thornton not having a closer mentality is based on, what, four consecutive bad outings from last April, when he blew a couple of saves and took a couple of losses? A total of four innings? His career OPS in the 9th inning is .666, vs. .660 overall. In save situations, it's .649, vs. .664 in non-save situations. Not saying there's no such thing as a closer mentality, or that Thornton is definitely cut out for the job, but can we really conclude anything about him either way from such a small sample? 

After those four bad games, his ERA was 7.71. Over the rest of the season, it was 2.95. It's possible that in some alternate-history version of the season in which he was allowed to keep closing all year, he would've been a complete disaster the whole way through. It's also possible that he would've made exactly the same turnaround had he been left alone. That's a lot easier for me to say with nothing riding on the answer than it would've been for the White Sox with the season on the line, so I don't blame them for not waiting around to find out when they had Sergio Santos available. (Apologies if I'm overlooking anything about this specific example–I haven't spent a lot of time studying Matt Thornton.)

Relievers are an unpredictable bunch, and a lot of them go from good to bad quickly without a change in role. Inevitably, some of them also go from good to bad quickly with a change in role. When sudden struggles and a role change coincide, it's easy to draw a connection between the two, but at least some of the time, it's bound to be noise. Short of a failed closer admitting that he couldn't perform because of the pressure, I'm not sure how we can ever know for sure when it's not.

Ken FunckTotally agree with you about Thornton, Ben. I'll cop to believing that there are guys who are destined to struggle in the closer role because of some ninth-inning mental block, but it's a condition that's significantly over-diagnosed and usually treatable over time.

What Mitch Williams said on Clubhouse Confidential last week was fascinating, in that he believes it's easier to get guys out in the ninth than in the eighth once you realize the pressure is on the hitter, not on the pitcher—you don't even need to throw strikes, since batters are more likely to get themselves out. Not that Mitch could have thrown strikes in the eighth inning, either…

Jason CollettePut Rafael Betancourt into that discussion as well, who has shown the skills for the role forever, but a handful of outings in Cleveland ruined that momentum.

As for Matt Thornton, he was struck by the Great Pumpkin on 4/8/11, and it was all downhill from there.

KG: Of course there is noise in the data, and it's quite possible that Thornton would have calmed down and figured out. It's possible that he still might at some point down the road. I personally think he deserves another shot, but I don't think April was just purely some random thing.

In some ways I'm playing devil's advocate. I was enjoying this thread quite a bit, and then I feared it was devolving into a trend I feel like I'm seeing that disturbs me. I don't know if it's the Moneyball movie or the HOF voting or general award season or whatever, but I feel like for many (and I'm talking generally, on the interwebs, not our team), the arguments have reverted to early-generation tomfoolery. Many have gone backwards to the argument that EVERY answer is in the data, and if you don't see that or agree with that, you are a caveman noob moron. The other side is just as guilty with Saber Boy accusations and get out of your basement and watch the game stupidity.

The data is mind-numbingly important. There are still plenty of breakthroughs to come from the data, and I'm convinced that many of them will come from people on this distribution list, but don't get trapped in the data. Don't just reject out of hand circumstantial evidence that cannot be proven with the data. That stuff is important too, and we can all learn from it. We can all get upset when someone like Jon Heyman shows a remarkable ability to break a story, yet at times shows a profound lack of understanding of the game. The easy reaction is to make fun and call him a moron and joke with all your friends in a corner. It's also an opportunity to educate, and more importantly to grow. The first person who wants to be a story breaker, who understands the value of picking up a telephone and creating a network of sources, AND understanding the value of sabermetrics and how to apply them… That person is going to be huge.

Sam MillerThe evolution of catcher defense measurements seems like a cautionary tale for all of us. Noise-to-signal ratio is generally massive in baseball, and each advance gets a little bit closer to the signal but not necessarily actually close, and sometimes leads to conclusions that are actually further away from being correct. Almost every argument I see seems a bit bad to me. Except "I dunno." "I dunno" is a pretty great argument.

JCKevin makes a great point. 2011 was my first season in clubhouses, and it gave me a new appreciation for the narratives I once mocked from my mom's basement while attempting to dehumanize the players. I still don't know how to qualify the human element with players, but I certainly have more respect for it now.

Jay JaffeRegarding Thornton, I thought it was pretty well-established—I'll have to dig for where I read it—that his early-season woes as closer were timed with an unsuccessful attempt to integrate a changeup into his reportoire.

JCData classifies 38 pitches as changeups in first 2 months and only 23 the rest of the season.

Adam SobseyI thought Jason Wojciechowski's ProGuestus piece did a great job in asking us to look for the balance between raw data and the inscrutable stuff that helps produce it.

JJYeah, here's a blog entry on it. Can't find the news article I recalled.

KFWhich begs the question: Did Coop tell Thornton to throw more changeups, or did Thornton choose to do so himself? If it's the latter, then maybe it highlights a guy who suddenly didn't trust his stuff and felt he had to do something different to succeed in the ninth.

JJI disagree with the latter line of thinking and feel like it's a mistake to try to get inside a player's head, particularly in attributing "insecurity." Logic suggests that it was a mutual decision between Thornton and Cooper to see if they couldn't add a new weapon, because that stuff happens all the time; the spring is a time to try stuff out—you can always scrap it and go back to what works. Somebody should have asked him about it, though. 

BL: Yes, I saw the post Jay linked to also, but I didn't include it in my email, since I suppose you could say that changing your approach when your role changes might be a manifestation of not having a closer mentality (unless it was something that came from Cooper). If it was something that came from Cooper, at least in part, you'd think he might've advised Guillen to let him work out the kinks before losing patience. Then again, the kinks kind of have to be worked out before the season starts. That's what spring training is for. 

Like Kevin, I was uncomfortable with a few of the earlier suggestions in this thread. Obviously, if a team decides a player isn't cut out for closing and removes him from the role, that lends some credence to the notion that he might not have the right mentality, but I'm not sure exactly how heavily to weight it. Team employees have more information and more access, but they're subject to the same biases as anyone else. Unless Thornton was spotted crying and screaming "I wanna be a setup man!" in a dark corner of the clubhouse, I'll still reserve judgment, since I'm not sold on anyone's ability to get inside his head. After all, people with the White Sox watched Thornton up close for his first four years in Chicago and decided he had what it took to close.

Jason's guest piece was great, and his views about most of this stuff mirror mine. The hardest part, I think, is being able to write something compelling when your answer is always "I don't know." 

KG: Totally agree that it's a mistake to get into a player's head, as it can lead to dangerous assumptions. I'm just saying the assumption that nothing going on in a player's head affects his play can be equally dangerous.

Jeremy GreenhouseBen, I obviously agree with your sentiments here. I remember watching all of Thornton's appearances at the beginning of the season and thinking how unlucky he was. I'm going through the video again.

Thornton's first appearance is in a 7-1 blowout. 0.2 innings scoreless. Disregard.

Second appearance, CHW 7, KC 6. Overpowers LHB Alex Gordon for a K. Gets 0-2 on Billly Butler, just misses a K, and then Butler sharply singles through the right side. Pinch runner steals second as A.J. Pierzynski drops the pitch. Thornton gets 1-2 on Kila, throws a low-and-outside fastball that hits its spot, but Kila reaches and serves it the other way for a double. Tie game. Thornton Gets Escobar, Pena, Getz, Aviles, and Cabrera to ground out. 

Third appearance, CHW 7, TB 4. Thornton gets 1-2 on RHB Elliot Johnson, jams him up and in, but Johnson bloops it to right, and the RF plays it for a single. Gets 1-2 on RHB Felipe Lopez, makes several hittable pitches that Lopez fouls off but eventually gets the K on a 10-pitch AB. Got 0-1 on Sam Fuld, but do not have video of the remaining pitches  in the AB. Fuld reached on an error by Alexei Ramirez. Thornton gets 1-2 on LHB Johnny Damon, throws a slider low and away that Damon reaches for and bloops to left. Juan Pierre drops it. 1-1 on RHB B.J. Upton, breaks his bat, but Upton gets a clean single. First pitch to LHB Dan Johnson is over the heart of the plate, and Johnson homers. Sox lose 9-7.

Here is a summary:

"Of the two botched 9th innings recorded by Thornton in past few days, the amount that can be blamed on him is negligible.  In Kansas City on Wednesday, Thornton induced weak contact from Kila Ka'aihue reaching for a pitch off the outside corner, and was rewarded with a game-tying double.  It stunk, but the Sox won, so people get over those sort of things. 

On Friday night facing Rays with a 3-run lead, after allowing a leadoff single, Thornton induced a groundout from Sam Fuld that the second-best defensive shortstop in baseball short-armed for an error. For the next batter, Thornton got a lazy fly ball out of Johnny Damon, only to have the second-best defensive shortstop in baseball miscommunicate with the third-best defensive left fielder in baseball, resulting in said elite-fielding left fielder letting the ball bounce in and out of his glove.  Even after all this, Thornton recovered to break Justin Upton's bat with a hard fastball, and witnessed it drop over the infield for an RBI single."

Fourth appearance, CHW 1, OAK 0. Gets 0-2 on RHB Adam LaRoche. LaRoche hammers a slider for a double. 2-0 on RHB Coco Crisp, Crisp gets his hands inside on a fastball and hits a nice line drive that is caught by the 1B. 2-0 on LHB Daric Barton, another hittable fastball that Barton hits to deep left and Juan Pierre drops on the warning track. Tie game. Yanked.

Fifth appearance, comes on with bases loaded, one out, CHW 4, OAK 2. Overpowers LHB Ryan Sweeney for a K. First pitch to Cliff Pennington jams him up and in, but Pennington fists it over the 2B's head for a two-run single. Tie game. 1-2 on DeJesus, groundout. Comes out for the next inning, Ellis grounds out, and then Thornton loses it. Five-pitch walk to RHB Conor Jackson, five-pitch walk to RHB Josh Willingham, 3-1 on RHB Coco Crisp, Crisp lines a fastball over the middle up the middle for a single. 2-2 on Barton, Barton singles.

Personally, I think Thornton was pretty awesome for most of it. He pitched like a LHB who throws 95-MPH fastballs for strikes. Most of the time, that's going to get the job done. There were a couple of times I wanted to question his pitch mix, but you need such a large sample of pitches to be able to say that a pitcher is pitching sub-optimally rather than randomizing his distribution. The in-play pitches to LaRoche and Johnson deserve some analysis. There were three crucial errors made behind him, Pierzynski being his catcher, a couple jam shots, and one hard-hit ball that got caught. His two walks actually occurred after he had blown all four saves. That's all I got.

BL: I noticed that Thornton had a .417 BABIP over his first five appearances, but I didn't do the work to see what kind of high BABIP it was. Jeremy did.

Derek CartyI think it's pretty obvious that the "human element" exists in baseball. The problem is, no one really knows what's going on inside a player's head. Sometimes, the player himself may not even be able to say for sure how external factors are impacting his performance. And even if we believe something is affecting him, what extent of his performance is attributable to this and what is mere random variation?

Yes, the human element exists, and it's fine if a writer or analysts wants to say that something like ninth-inning mentality exists (it likely does, to some extent), but don't try to pretend like you know that a certain player has it or doesn't have it unless you have a really good reason for doing so (an official for a team, for example, might have such a reason, whereas a MSM writer might not). Don't say that Matt Thornton doesn't have the mentality because you saw him throw four innings as closer in the beginning of 2011 and that's your entire basis for your opinion. It seems a lot of times MSM analysts who don't understand stats and don't care to learn about them use this "human element" stuff as a crutch. Because they don't have something truly meaningful to say, they'll spew some overstated crap about the human element, maybe attempting to support it by using some meaningless, small sample size data or split.

Even worse is when former players-turned-analysts talk about their own experiences playing the game—their memories of which can sometimes become warped over time—and generalize that experience to other players. Everyone has their own unique psychology, and just because you were a player yourself doesn't necessarily mean you have any idea what's going on inside the head of another player. 

I think the other thing that goes overlooked a lot is that MLB players, as a group, are inherently very good at dealing with pressure situations. They've been facing pressure their entire lives, and part of the reason why they are MLB players to begin with is because they dealt with that pressure effectively enough to succeed in high school and college and up through the minors to the point where they're even being considered for, say, a ninth-inning role. Writers like to say that this guy won't succeed in this role for X-Y-Z asinine reasons, but unless you have a truly legitimate reason for thinking that, odds are that the player will succeed because his track record of dealing with pressure, as a human being, is really, really good.

Tommy BennettI think the heart of this argument is about how much weight to give to various pieces of evidence. Everyone agrees that several years of success as a set-up man are good evidence that a pitcher is ready to take on closing duties. Everyone agrees that a terrible debut as a closer provides at least some evidence to suggest that the pitcher is less well-suited to be a closer than you would have thought before the lousy debut. Information from teams and knowledge of particular pitcher's makeup give a similar indication. 

So the question is how much you weight one against the other. In general, I think it's better to rely on the former type of evidence, since it's the one that's been proven to have the most straightforward predictive effect. That does not mean there aren't people out there who can pick out—before the fact—the pitchers who lack a closer mentality. But if those guys are out there, what they are able to do is very different from observing after the fact that a guy failed when thrust into the closer role and assuming from there that he lacked the closer mentality. And if those guys really do exist, I'm willing to bet they're gainfully employed by major-league teams and not sharing their secrets. 

Thank you for reading

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So, Dan Johnson hits two MLB home runs on the season...

His first, on April 8th, against fellow lefty Matt Thornton, helps change the White Sox bullpen configuration.

His second, 180 days later, changes the tenor of the A.L. wildcard race during the "most exciting hour of the regular season."

Quite an impactful -0.8 WAR season!
Good article and great discussion, thanks everyone. Is there
any statistical indication that age actually improves save rate, at least until physical decline sets in ? Here's one sample : Ramon Ramirez was 1 for 11 in scatttered save chances in first 4 years, 7 for 8 since then. Matt Thornton was 9 for 29 before going 8 for 10 in 2010.
Any relief pitcher who's used in setup or specialist roles will tend to have low save rates, since they often enter in a save situation in the 8th (or earlier), but they'll hand the ball over to the closer in the 9th and not be credited with a save. However, if they fail, they still get charged with a blown save.
Sample size. I don't think 19 appearances is enough to draw any conclusion whatsoever.
I don't think it's any different than how things work at your job. You know who you can trust to stay calm in a stressful situation, who will let a bad mistake stay in his head, who has a comfort zone that he won't stray from. This affects people of all skill levels. Why would it be any different with ballplayers?
I think Derek (and commenter Tarakas) addressed that. By the time a ballplayer gets to be a successful setup man, he's already proven that he can handle intense pressure--probably more intense than most people face in their day-to-day jobs, even in crunch time.
I wonder if that is the case. Certainly when I used to follow golf, there were players who were seen as not being able to handle the pressure of closing out a major championship - people like Scott "Hoch as in Choke". Obviously, it's difficult to tell when someone has blown an opportunity due to pressure, and when they executed well, but just got a poor result, but I wouldn't assume that it's automatically the case that everyone who can pitch competently can handle the pressure of closing.
What if you compiled data from 1955 and every tenth year thereafter and asked a simple question, "When a team led after 8 innings, what was the percentage of victory in those circumstances?"

In theory, if the closer is a truly specialized class of pitcher, shouldn't success rates increase over the years as the role developed/

And what if it turns out that success rates aren't a whole different?

Are there any insights to be gained from this approach?
Joe Posnanski looked into that in November of 2010. He found that the percentage of ninth-inning leads that help up in 2010 was 95.5. In 1952, the percentage was... also 95.5
Colin looked at a similar question in his great piece on closers.
Of course human factors are part of a player's performance. But I would guess most players who can't handle pressure never make it to the majors--there is plenty of pressure in high school, college, and the minors.

Too often, we try to make players fit our narratives. Anyone who plays a season of a baseball sim game-by-game see this.

Years ago, I played out a season using the old "Statis-pro" game. I carried Dan Dreissen as a back up first baseman and pinch hitter. Throughout the season, and especially the pennant stretch, Dreissen had big hits for me, including several late inning pinch hit home runs that led to come from behind victories in crucial games down the pennant stretch. When it mattered, his hitting performance far exceeded the numbers on his card. He won me the season.

If this happened in real life, we would marvel at his clutch hitting ability, the strength of character that led to his exemplary ability to always come through when his team needed him.

But in reality, he was a piece of cardboard on a run of good luck in a small sample, with no more character than any other piece of cardboard. After you see enough pieces of cardboard (or collections of code in a computer sim) exhibit by chance the same human tendencies we like to attribute to character, you gain perspective.(That team's dependable go to pitcher in big games was staff ace Jim Clancy, who like a Chris Carpenter or Curt Schilling always rose to give me a great performance on the mound when I needed it).

I'm sure intangibles and character exist in real life--but all too often, when we talk about them, they are simply stories we impose on small samples of data. It's easy to look at my cardboard Jim Clancy mowing down batters in a simulated post season game and realize that was simply luck. When you are dealing with real players, talking to them in the clubhouse or watching them as fans at a game, it is much harder to separate luck from character.

All Matt Thornton demonstrated last year was that a short reliever can have a few consecutive outings that look rough in a boxscore. Anyone who has played a sim knows that can happen by random chance, too.
This is right on the money.
Call it "the many Matt Thorntons." On any given day, a player may be: Trying something new, getting familiar with a new role, feeling comfortable with a new role, feeling nervous, feeling confident, sleeping late and forgetting to get the standard double shot espresso on the way to the park, mulling over a fight with wife/friend/family, dealing with a twinge in some joint or muscle that isn't even worth reporting, fighting a low level virus that isn't even noticed, etc. etc.

Within THAT kind of noise, who can pick what it was that really mattered if Mr. Thornton did poorly on a stretch of days, whatever the inning.

I do believe another Matt Thornton could eventually be: Handling the implications of previous failures, whether due to luck or not. At that point in a hypothetical future, he may become done as a closer only because nobody will have the investment to let him work it out anymore. Not even a sabermetician.

So perhaps the closer mentality is a function both of measurable skills and happenstance at the very earliest stages of the trial run: Half talent, half luck. Still reality, whatever the outcome.
Can't help but think of Brandon League's 2011 season in this discussion. Coming into 2011, he had 13 blown saves in 21 save opportunities. What if his horrific stretch from May 8-13, 2011, didn't come after nailing down 9 saves to start the season? He likely would've been removed from the job, labeled as not psychologically cut out for the closer role, and probably never given another shot at it. Instead, he went on to be probably the best closer in the game the rest of the season.

Having grown up in the midst of the Latroy Hawkins-Eddie Guardado dichotomy in Minnesota, which gave a pretty clear appearance that mentality is more important than ability when it comes to closing, I had long thought that some guys just "have it" and others don't. But the evidence to the contrary just keeps mounting. (As Rany's Farnsworth example highlights, in addition to Mr. League.)

Can we stop citing numbers like this which appear to suggest someone can't close, given that you can blow a save if you lose the lead in the 7th or 8th, but can't get credit for the save unless you finish the game. If we must use this data, surely we should include holds as being a successful result for these pitchers.
Thank you for reminding me how throughly snake bitten
Thornton was last year at the start. I watched all of those games because I had invested $11 in Thornton to be my closer. I remember those 0-2 pitches and those unlucky breaks, but what bothered me most about Thornton was his body language. He looked like he'd have rather been anywhere, but on that mound. The year before, in a set-up role, he was one-two-three with hard, well located balls that righties and lefties were struggling with. He was dominant. Dan Johnson is a fairly patient hitter, but he doesn't see many lefties anymore. He wasn't going to wait around on Thornton. First pitch he could see he put his second best swing of the season on it. That was a no doubter. Johnson had disappointed me on more than one occasion as well so that one hurt me more than most. Ozzie tried to hang on with Thornton, but the truth is he probably saw what I think I saw; the guy was no longer challenging hitters and nibblers invariably don't get the call or get beat on cheap crap. I hated it at the time, but Thornton earned his demotion. I only regretted ignoring Santos for so long while watching this debacle. I ended up winning my league, but no thanks to Matt. I traded him for an injured Luke Scott just to get him off my roster and onto a team that wouldn't hurt me if he got his job back. Now I have Addison Reed. How much do you want to bet Thornton is a thorn in my side again this year? Not anybody can close, that's a fact in my mind, but more often than not, pitchers who you think have no business closing are tougher mentally than we ever give them credit for and get the job done. Thornton was not tough enough mentally in my opinion. All you need is decent control and to not be afraid to fail. And though my first vote would be for Tim Raines if I had a ballot, I would absolutely vote for Lee Arthur Smith for the Hall as well.
"The first person who wants to be a story breaker, who understands the value of picking up a telephone and creating a network of sources, AND understanding the value of sabermetrics and how to apply them... That person is going to be huge."

Isn't that person Peter Gammons? And isn't he already kind of huge?
Also, thanks to Adam Sobsey for the totally gratuitous shout-out. Your check is in the mail.

I think the line we have to be careful to draw is between "you didn't prove that" and "that's not true." This isn't the legal system, where we treat the former as the latter because ... well, because we have to. Because a conclusion *must* be reached.

In these corners, the only pressure to reach a conclusion is, as Ben says here and as Matt Klaassen said to me on Twitter in the aftermath of the aforementioned ProGUESTus piece, that writing "I dunno" all the time is boring. Like really boring. But outside of that, we don't *need* a thumbs-up or down at the end of the day. It's perfectly o.k. for the question to remain unsettled.

Which means: it's equivalently o.k. to tell someone writing about psychology that they're ascribing effects to causes that their data don't support as the sole or even necessarily dominant factors and to leave things at that. We don't know any better than the offending "analyst" about the psychology of the situation. What we do know (or at least what we are/should be willing to express in print in a way that said analyst is not) is that he doesn't and can't know, and we should be telling him that. (Ideally with as little of the rancor that KG identifies as a bit of an epidemic on Twitter these days as possible, but I'm kind of agnostic on the question. Some people shut down when they're being yelled at, some people don't respond until they're yelled at, and some people will never respond at all, meaning that the yelling is just for our own entertainment and catharsis. Which is fine. I ascribe no moral value, negative or positive, to any of this.)

For what it's worth, I think a lot of the over-confidence on "our" side comes as a simple reaction to the same (or worse) on "the other" side. ("The other" side, to the extent that they spend as much time unhealthily obsessing over these meta-questions as I tend to do, might say the same back at us. Who knows. It's a dinosaur/egg question, I guess. (Though I will point out that one "side" has a lot more dinosaurs.)) As I type this, KG retweeted someone making this comment: "closer mentality definitely exists" -- why so [sure]?
That someone was a professional baseball player. That's the thing. When I talk to people inside the game, they'll all tell you it exists and it matters. Not just the dinosaurs. People who come from the numbers side as well. I've had more than one tell me how much how they saw the game changed once they got closer to it.
Not to take sides on the question one way or the other, but are we not agreed on the fact that one of the worst groups at analyzing professional baseball players is professional baseball players?
Between the specialization of genius, the learned culture of baseball, the Crash Davis Media Effect, and what Derek mentioned about universalization of experience, players analyzing themselves or other players should probably be taken with as huge a grain of salt as anyone else analyzing them.

I think we should respect the possibility that teams have profiles of players that affect their decision-making (e.g. the A's chose Brian Fuentes over Grant Balfour as their closer in Andrew Bailey's absence last year -- we should leave room for the possibility that they know something about Balfour, although of course Billy Beane's past approach to closers might raise some doubt on this front), and I suppose it's possible that someone of Don Cooper's level of experience can start to develop valuable intuitions that may not reduce to simple explanations of how/why, but in general, crowd-sourcing a deep psychological question to a bunch of people who got their B.A.s in the Sally League majoring in Hitting or Pitching strikes me as having similar value to asking 200 hometown fans who watch 95% of their games on TV and the other 5% from the right-field bleachers how good a third-baseman's defense is. Why would we expect them to know?

The impossibility of dissing your own players in print prevents this, but I'd like to see "he chokes under the pressure of closing" applied non-post-hoc. I was going to write a thing before I remembered that Ben already said it: "[P]eople with the White Sox watched Thornton up close for his first four years in Chicago [jw: pitching in many many tight situations] and decided he had what it took to close."
One of the dangers from reading too much into the experience of players on something like this is that their perspectives are developed under a lens where they are highly motivated to believe that the closer mentality is more important than it is.

It's a form of professional advancement, and it wouldn't do a lot for a veteran pitcher's self-image to think of all the work he put in to get where he is, only to be told he could have done just as good a job when he was fresh out of AAA. Consider that it's a career path where a player's physical attributes often peak at the beginning of his career, followed by very hard work to maintain his performance, and by age 30, his work is usually going more toward slowing his decline than improving his performance. It would have to be tough thinking that you're entering the downside of your career at around the same time as people in many other fields are just starting theirs.

However, while the physical can be measured (if a guy's lost 2 MPH on his fastball, that's a fact that's hard to deny), the mental can't, and that makes it susceptible to faulty memory. Your 32 year-old self doesn't want to believe that your 24 year-old self was better at his job then than you are now, so it's easy to mentally downplay distant past achievements in favor of recent achievements. Similarly, if you see your ability degrading, a belief in the importance of something like the closer mentality as a reason why the 23 year-old kid throwing 98 shouldn't replace you just yet.

Ballplayers are people, which means they do feel pressure and undoubtedly have a range in how they respond to pressure, but they're also people, and subject to the types of biases and reconstruction of their own memories that can make them terrible sources for analyzing their minds and those of their peers.

I think to have a proper discussion on the topic, we need to demystify the Closer Mentality. How do we define it. There's no cosmic force that imbues certain pitchers with added velocity in the ninth while causing slider-amnesia in others. But by the same token, all players, with the possible exception of Albert Pujols, are human. Pressure is one thing, but how would a player who's comfortable in high-leverage eighth inning situations suddenly be overwhelmed in save situations, when he almost certainly had to endure far more pressure competing for his first MLB job? Is there a mental block for some players, and if so, how common is it? Are we looking at a rare psychological quirk here, or something that exists strongly, but is usually weeded out before MLB? Or, is it really so big a jump in pressure that it trumps things like the risk of unemployment for rookies, or other high-leverage situations for teams in postseason hunts?
Jason, the only thing I object to in your post is that your number is much, much lower than mine.
Jason - you bring up/brought up some great points. One thing about writing for an audience however (and I know you know this) is that to be taken seriously, you need to write with some confidence. You can't write "I think", or you come across as wishy-washy. You need to be forceful and take a position and then defend that position. The fault lies in readers who expect infallibility.

Similarly, the fault may not lie in the nascent closer but in his teammates and other interested observers, who expect him to be right from the get-go. To close first and ask questions later. If they don't feel that he can get the job done, the team brands him as lacking, much like someone might not have what it takes to be a great leader even in he/she has grand visions at night. IF others cannot be persuaded to follow, that person will never be a leader. If others don't believe that a person can close, he won't consistently close.

Others brought up the fact that these players showed the ability to compete countless times in the past, but in those situations they also had the belief of their teammates. Now, for the first time, that belief may be faltering. That can have an effect. It certainly does with goalies in the NHL.

As much data analysis and science we try to bring to the game (and many other subjects in the humanities), there is an element of art that cannot be perfectly quantified. Maybe - hopefully - that is why we love the game and many other things so much. But we still have to defend a position to be taken seriously more than once. Maybe you will be wrong, but that's OK.

What made your ProGUESTUS piece work is that you took a position that we do not know very strongly and defended that position well. You can do that only once, however. To keep writing well (to keep the reader reading you well) you will need something else to take a position on. I believe in you - now go write, lead, close.
I've said this before: the reason one cannot find evidence of persistent "closer mentality"/clutch/whatever is that the psychological effects are inherently transient. The pressure a pitcher feels the first time they've got a lead on the line is nothing like their 100th. The intensity of a hitter's first 9th-inning World Series at-bat is nothing like the 10th.

Pressure might help someone like David Ortiz focus in clutch situations... until they get used to it, or they start to expect it, or they show up in a bad frame of mind, and then it's back to normal. Pressure might crush someone like Farnsworth at first, then they come back a couple years later a bit more mature or confident, and hey suddenly closin' ain't no thang. Eventually it all comes out in the wash, so data people say "there's no such thing as clutch!" because in the long term it evens out.

So can anyone close? Yes, given enough opportunities. Of course real teams can't afford to wait around for things to get fixed (nor is 'just keep letting him take his lumps, he'll figure it out' always the right approach), so they do, and should, try to put people in those situations who can handle it psychologically from the get-go, and remove those who can't. In that sense, the "closer mentality" is real. But it doesn't make a real difference in the long-term so it's not worth paying a premium for.
My recollection of watching Thornton pitch against the A's last year is that he had trouble getting his breaking pitch over and the A's hitters laid off of it. They couldn't always catch up with his heater but they fouled some off and hit a few. They were pretty good at laying off the fastballs up and out of the zone which is tough since he hit 96. He was still a nasty pitcher but not as dominant as before.

I really think most of these "character" issues are really our gloss on underlying physical issues.
It seems to me that Hawkins did much better in save situations than other games during 2000-01, his first stint as closer, but I've not gone through the game logs to show it.