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In recent years, with the advent of the PITCHf/x system, people have begun to complain about the calls of home plate umpires more often—or at least more accurately. Make no mistake: questioning the umpires’ judgment is a concept as old as the game itself, and QuesTec technology has been used for nearly a decade to assess the home-plate performance of the men in blue. PITCHf/x, however, has changed the outlook for the media and common fans alike, providing a very quick way to check whether an umpire is calling a “fair” strike zone during the game being played and thereby confirming or refuting someone’s feelings on specific pitches in real time. A few clicks, and all the necessary information is available at your fingertips, whenever you want it and wherever you are.

Mike Fast has repeatedly—and in my judgment, convincingly—explained why we can’t take at face value what we see on MLB Gameday, mainly because of potential calibration issues, though this hasn’t exactly stopped people from doing it. There’s absolutely no question that home plate umpires can impact a game, sometimes dramatically, and there’s no question that they will occasionally botch calls. In fact, Tony La Russa himself has complained about “two-strike zones” during the 2011 playoffs, and various folks on Twitter remarked during World Series Game 7 that Jerry Layne might have been squeezing the Rangers’ pitchers a little more than their counterparts, citing this graph from the excellent This sparked, among others, this tweet by Brilliant Sportswriter Joe Posnanski.

His question—“Would baseball be better or worse if Fox Track or its ilk determined balls and strikes?”—seems relatively tame, and the obvious answer is that we still don’t have the technology to guarantee “perfect calls,” even if we did want to abolish umpires. In fact, as I’ve said, we can’t even guarantee that those graphs are sufficiently precise to judge Layne’s work with the accuracy it requires. Thereby, regardless of your feelings on the matter, we don’t have a practical alternative to home plate umpires yet.

That being said, let’s assume, for the sake of discussion, that those concerns don’t exist. Let’s assume those graphs are perfectly accurate, and let’s assume that we do have the required technology. (After all, I’m fairly confident that MLB could have a system in place within a few years, at most, if the powers-that-be really wanted to implement one). Posnanski’s question is still valid when adapted to that scenario: If MLB had an available and reliable pitch tracking system, would you use it replace home plate umpires? Not as easy to answer as before.

Some people’s objection to automated systems is that the human element is the beauty of the game (Here’s an example.) This doesn’t seem right to me: I don’t think anybody is excited about umpire errors, and I really don’t think that the beauty of the game resides in botched calls that alter the course of a game. In fact, I believe that the beauty of the game lies in watching great athletes perform at the highest levels—that’s the human element we pay to watch and enjoy. Umpires should go unnoticed, if possible. The best umpires are often those whose names don’t sound too familiar, because they let the game be the story without drawing attention to themselves, either because of their personality (think Joe West) or because of their erratic behavior (think, well, about a dozen names here). I will state here that I am completely in favor of the implementation of instant replay for close plays on the bases, for example. I don’t care if someone feels it’s “beautiful”—an erroneous call like Ron Kulpa’s on the Napoli-Holliday play at first base in Game 3 of the World Series should simply not take place, and we already have the instruments to prevent it. (As an aside, I think it would speed up the game instead of slowing it down by obviating all the unnecessary managerial arguments.)

All that said, I think home plate is a different creature.

The reason why I say this is that being able to expand the strike zone is not luck or chance but a skill exhibited by both pitchers and catchers. J-Doug showed that some pitchers consistently have bigger or smaller strike zones than their colleagues, and a cursory look at the lists seems to confirm the belief that this skill is inherently tied to command and the ability to hit the catcher’s mitt with multiple offerings.

Mike Fast (here) and Max Marchi (here and here) have shown that framing pitches is also a very important skill. There’s a reason why Greg Maddux anecdotally preferred Henry Blanco behind the plate instead of Javy Lopez, even though it clearly meant taking a hit in run support. Being able to expand the zone therefore isn’t random but part of a reward that comes with extra command (for pitchers) and a better fielding tool (for catchers) rather than sheer entropy and chance. An automated strike zone would largely nullify catcher defense, making only a strong arm and good blocking skills necessary and thus modifying the characteristics of the position. We’d see more Posadas and fewer Lucroys. And to channel my inner Helen Lovejoy, won’t anyone think of the Molinas? But is this what we want? Do we want to radically change the meaning of a position?

I would add that “selling the call” is part of all sports, but baseball and a few others also require the umpire to be not only an enforcer of the rules but a judge of intentions. The check-swing call is an example of this, as the umpire is supposed to analyze not just simple actions, but intentions as well. This is a quality baseball has in common with its British cousin, cricket. In cricket, a batter may be out if he shields the wickets from the ball with his shin guards (the elimination is termed LBW, or leg-before-wicket), and it’s strictly a judgment call by the umpire, whose decision is often greatly influenced not only by the delivery and where the ball hits, but also but the bowler’s and the batsman’s reactions. As a result, a real relationship develops between the players and the umpire, which players can exploit to gain advantages if they properly execute their plays.

Likewise, in baseball some of the advantages that a battery gains are the deserved byproducts of skill, and an automated strike zone would eliminate this fascinating aspect of the duel at the plate. Also: part of the greatness of Mariano Rivera, Greg Maddux, and Roy Halladay comes from their ability to expand the zone, which isn’t just an umpire gift coming from nowhere but a component of their mitt-hitting talent. While it is certainly infuriating to see at times, the way such pitchers carve hitters and umpires alike by painting the strike zone has to be appreciated. For a long time, the duel between the batter and the battery has had certain dynamics and certain characteristics, and an automated strike zone would radically change that relationship. Personally, I have grown to appreciate pitchers and catchers who can control the strike zone. Baseball is a game of deception, and controlling the strike zone is a fine nuance that I’d hate to lose.

I understand and am sympathetic to the counter-argument. “Fairness” is important, and having the same strike zone for every pitcher, every batter, and every catcher would definitely make the game feel fairer, unless we accept that some people earn the right to a different zone. You could in fact argue that it’s fair that some pitchers and catchers earn the benefit of the doubt. These are different points of view, of course, and there are good arguments on both sides of the issue. This is why I’m a little on the fence with this one: surely fairness should be pursued at all times, but I would hate to lose the fascinating dynamics of the matchup and thereby revolutionize the catching position (perhaps with unintended consequences), just as I would hate to discount an actual skill exhibited by pitchers and catchers.

Perhaps an intermediate (and probably unsatisfying for all involved) solution would be to automate “clear” strikes and balls in order to avoid ridiculous calls (see Livan Hernandez in a well-known situation) and allow the umpires to evaluate and reward (or punish) the calls around the black based on traditional judgment methods. After all, the calls that really inflame people’s passions are the obvious and clear ones, not the extra inch or so given out occasionally, and if we can avoid the obviously errant calls, it might be good enough for everyone.

Whatever your point of view, it’s important to consider the possibility that eliminating the home plate umpire wouldn’t have only positive outcomes and might change the way we see the game, which requires in-depth considerations that go beyond visceral reactions like, “OMG that was a ball! Bring on the Robots!” And not because of the “human element” of mistakes, but because there are factors that go beyond right and wrong, strike and ball. As usual, there are shades of gray.

Assuming J-Doug’s research is correct, Rivera’s RA between 2008 and 2010 would have nearly doubled with infallible robot umpires in place. Would you be willing to wipe out the next Mariano Rivera (or at least mitigate his greatness) in the interest of supposed fairness? Maybe Mariano would have found a way to be just as great, but maybe not. He probably would have taken at least a hit in value (pardon the pun) along with most other command-oriented pitchers, while wilder ones might have emerged mostly unscathed. Is that really fairness, or is it disregard for a skill? I don’t have an answer for that, but it’s something that needs to be considered. I feel that errors are unfair, but plays where skills are involved don’t necessarily strike me as errors. It seems like whichever way we go, there are gains to be had and losses to be suffered. Which solution would offer the best net gains?

If you’ve read to this point, you might be disappointed that I don’t have a clear-cut answer, but I think it comes down to our personal tastes. My point is really that such a decision should go beyond the simple desire to have rigidly standardized strike zones and incorporate an understanding what we look for and appreciate in the game. We might eliminate blatant errors, but in the process, we could incur some collateral damage that might be too much for some of us to take. You know, I kind of like watching the way that Mariano guy goes about his business.

Thank you for reading

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Interesting points. However, I think robot improved strike umpiring would improve the game. I'm willing to trade the boringness of that for the frustration of random unfairness that comes from imperfect strike zone umpiring.

However, we would still need a head umpire to keep the pace of the game in check.
So you're saying here that certain players like Mo have "earned," or should earn, exemptions from the rules defining the strike zone?

the NBA-ification of MLB continues....
Even if Rivera (and perhaps others, such as Greg Maddux or Tom Glavine) has benefited from a more generous strike zone than other pitchers get from the umpires, I do not accept the premise that robot ball/strike calls would have doubled his ERA. Rivera, like Maddux and Glavine before him, has incredible control; I have no doubt that he would adjust to the actual called strike zone, and would do so far better than most pitchers. Certainly getting fewer strike calls would mean that his effectiveness would decrease, but I believe that the effect would only be marginal.
This reminds me of a point hilariously made by Supreme Court Justice Antonin Scalia, of all people, when a PGA golfer sued for the right to use a golf cart during the competition. The Court found itself investigating whether walking is "fundamental" to the game of golf. Scalia wrote that "either out of humility or out of self-respect (one or the other) the Court should decline to answer incredibly difficult and incredibly silly question." The rules of sports are arbitrary; there can be no right answer.

Baseball has a written and an unwritten rulebook. In the written rulebook, balls and strikes are determined by the physical path of the ball relative to the plate and the batter. In the unwritten rulebook, they depend on the reputation of the pitcher, the framing skill of the catcher, and the tastes of the umpire. Neither set of rules is fundamentally "right." I prefer the rule with more character, which makes the game more entertaining.
The quote should say "this" between "answer" and "incredibly." Sorry for the typo.
I appreciate your thought, Nathan, and agree with a lot of it. However, there is not much evidence that the strike zone depends on the reputation of the pitcher, though that is commonly claimed. There is evidence that the strike zone depends to some extent on whether the pitcher hits the catcher target. Pitchers who can do that also tend to have reputation as better pitchers, and deservedly so, but that may be where the claim arises about a pitcher's reputation mattering for the strike zone calls.
Bring on the robots to call it. Accuracy is more important.
I believe you mean Greg Maddux preferred Eddie Perez catching him rather than Javy Lopez seeing how Eddie was Maddux's personal catcher for most of the years Maddux played for the Braves.