I’m flipping the script a bit this week. Y’all brought interesting names to the table in the comments section last week, and while I normally choose an individual player on whom to focus based upon your suggestions, I felt the need to go off the board. Quite simply, it’s because right-hander Jake Arrieta laid waste to Major League Baseball last month. He wasn’t talked about enough in fantasy circles, but after flirting with no-hitters in back-to-back outings, he’s on the tip of every fantasy owner’s tongue.

Through 39 2/3 innings in the month of June, Arrieta compiled a 0.92 ERA with 48 strikeouts and only six walks. He’s gone four consecutive starts in which he’s thrown at least seven innings and struck out nine. Fantasy owners have taken notice, too, as the 28-year-old hurler is now owned in 83.5 percent of ESPN leagues (as of Monday evening). It’s a number that has increased dramatically in the past couple weeks, and owners have begun to ask whether Arrieta is someone to simply plug-and-play while he’s scorching hot, or if this breakout is something more permanent.

Good news: That’s what we attempt to determine in this space every week. I also reached out to a couple of other BP writers to help shed some light on Arrieta’s recent performance, offering multiple distinct perspectives on what’s happening on the North Side of Chicago.

Let’s do this.


Almost exactly a year ago, the Chicago Cubs acquired right-hander Jake Arrieta in a deal that sent veteran Scott Feldman and Steve Clevenger to the Baltimore Orioles. Arrieta was a former top prospect, but he had acquired the dreaded “bust” label after struggling for his first four seasons in the big leagues. In 358 innings with Baltimore, he had a 5.46 ERA and was walking 15.3 percent of the batters he faced in 2013 before the trade.

It was a mess of a situation. The Cubs, however, saw Arrieta’s natural ability and wagered they could fix him. The change-of-scenery deal is a gamble that many organizations have made over the years; it doesn’t always pay off. It appears the Cubs may reap significant dividends from this deal, though, given his recent dominant performance. Some articles have even begun wondering if Arrieta could be the next “ace” for the Chicago Cubs, which illustrates both the knee-jerk hyperbolic nature of our sports media and just how stellar the right-hander has been over the past couple months. Newspapers are no longer asking if Arrieta is going to make it as a big leaguer, but rather if he’s going to be elite.

Command and control have historically been troublesome for Arrieta. He actually held opposing hitters to a .212 batting average in 2013—which was 11th-best among 157 starters who threw at least 70 innings—but his 12.7 percent walk rate was the second-highest in all of baseball. He wasn’t consistent with his mechanics. Thus, he issued too many free passes undermined his above-average stuff that was largely handcuffing hitters. He ended the 2013 season with a 4.78 ERA.

Are those struggles merely a thing of the past? Our own Doug Thorburn says certain mechanical adjustments this year have allowed Arrieta to be more consistent, leading to better control and improved results:

The most critical variable in pitching mechanics is timing, and a pitcher's ability to repeat his delivery is at the root of pitch command. The winding road of Jake Arrieta boils down to just this aspect. In seasons past, Arrieta has had an inconsistent pace to the plate with momentum that could be downright slow at times. The erratic timing wreaked havoc on his release point, and the issue was magnified by his volatile positioning. Arrieta has a very closed stride that actually lines up well with his personal signature, but his stride angle can fall off-track.

He added some burst to his stride this season, but with it came an imbalance in which the right-hander would lean back toward second base as he transitioned out of maximum leg lift (the “rock-n-roll” style). The issue was quite pronounced on May 13 against the Cardinals, a game in which Arrieta consistently missed targets with elevated pitches and finished with five walks on the day. He ironed out the issue over the past several weeks, working with pitching coach Chris Bosio to maintain balance while leading with the hip, executing a smoother transition during the lift phase. His balance has improved, and Arrieta has been using the quicker pace to the plate with much greater ease of repetition.

It bodes well for Arrieta's future that he has uncovered a repeatable timing pattern. Such discoveries can be fleeting, but the Cubs now have a template on which to anchor. At 95 mph, his fastball already has the raw velocity to beat MLB hitters, and the ability to command that level of heat can be devastating. Fastball command is an integral aspect of pitching, and the stakes are raised for those pitchers who sit on the right-tail of the velo curve.

Those mechanical adjustments were on display as he twirled a gem in Boston. They have helped him slash his walk rate in half to 6.3 percent this year and have also aided in his increased consistency when working through a batting order multiple times.

Strangely, though, as of Monday morning, the numbers suggest Arrieta hasn’t been throwing significantly more pitches in the strike zone. In fact, according to Brooks Baseball*, his zone percentage is down an infinitesimal amount from 39.87 percent in 2013 to 39.37 percent in 2014. He is getting more swings at pitches outside the zone (30.5 percent to 33.5 percent), but such an uptick is not enough to account for the stark decline in walks. Instead, he’s throwing more first-pitch strikes with his fastball and slider, which is allowing him to work outside the zone later in the at-bat when he’s searching for the punchout.

Strikeouts have certainly become more prevalent this year. His current 29.0 percent strikeout rate ranks fourth in Major League Baseball among pitchers with at least 50 innings, sandwiched directly between Yu Darvish and Max Scherzer. It’s a product of working ahead in the count and an increased usage of his slider and curveball.



















Arrieta is clearly leaning on his breaking pitches more heavily, specifically his slider, and he understandably gets more whiffs on his curveball and slider than he does his fastball.

Thus, not only is he throwing pitches more often on which he generates more swings-and-misses, but he’s actually missing bats more than he was a year ago on those same offerings. It’s no wonder his strikeout numbers have soared this season. His control/command is better, he’s throwing more sliders and curveballs, and he’s getting more whiffs on those sliders and curveballs. That’s a good combination.

While that all sounds lovely, perhaps the biggest reason Jake Arrieta has lowered his earned run average has been an improved strand rate. He owns an 82.0 percent strand rate this year, which is drastically higher than his career 68.6 percent strand rate. Many people simply explain away strand rate as a “luck” statistic, but that doesn’t explain much with Arrieta. He sustained a strand rate that was dramatically below the league-average for several years.

He struggled in higher-leverage situations over the years, allowing one mistake to seemingly linger in his head and later compound into more mistakes. Opposing hitters have managed a healthy .333/.436/.604 slash line in high-leverage situations over his career. Our own Mauricio Rubio explains, “The game is hyper-mental for him. He very much lives in his own head.” This suggests it was paramount for Arrieta to improve the mental side of his game before he could see the on-the-field results.

This article from this season expands upon that point, quoting Arrieta as saying, “I was just at a point during my career with Baltimore where I was living and dying pretty much with every pitch I threw. After a game, I would go home and I would beat myself up just miserably.”

Such a quotation (and the article as a whole) does not merely indicate that the mental perspective for the right-hander has improved, but it also offers anecdotal evidence that the change of scenery was necessary. Arrieta was perhaps hindering his own success in Baltimore and his move to Chicago offered a chance to hit the reset button on his career.

However, Mauricio Rubio wants to see how Arrieta responds when he’s not merely dealing with success, which is pretty much all he’s seen this season—and to an extreme degree as of late. Rubio says, “I'm still waiting to see how his mechanics and command do after a bad start. I think he has broken down when things go poorly, they haven't really gone poorly yet.”

Perhaps that will be the ultimate test to determine whether Jake Arrieta has truly arrived as a stud fantasy producer. Everything seems to be in place. He’s still throwing in the mid-90s, his swinging-strike rate has increased, his walk rate has decreased, and he’s understanding how to utilize his best pitch (his slider). His dominance is reflected in his 2.05 FIP, which ranks behind only Clayton Kershaw and Felix Hernandez. If the mental aspect of his game has truly turned a corner this year and Arrieta is more confident in himself and his abilities, he could be poised to become at least a top-30 fantasy starter for the remainder of the season. Considering he’s still available on the waiver wire in some leagues, that’s a no-brainer pickup.

Buyer’s Advice: BUY
I recognize that I just said we need to see how Arrieta responds after he fails before we can truly “buy” him as an elite fantasy starter, but if he’s on the waiver wire, fantasy owners should grab him immediately before he’s gone. While he may not be elite, he’s certainly ownable in all leagues. On the other hand, those fantasy owners who may want to target the right-hander via the trade market have the flexibility to wait for him to fail and to see how he responds; however, it may not be wise to wait. If he continues to dominate the National League in the month of July, his price tag is only going to increase. The price may only be reasonable now, and I like the statistical profile enough and the improved mechanics enough to take a chance that he’ll mentally be able to deal with failure and bounce back in Chicago. In short, I like the profile enough to take a chance that he’s worth the increasing price. The stuff is real. If the mental portion of the game follows, the National League had better watch out.

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*Note: Brooks Baseball statistics are from before Monday's outing.

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It seemed to me that Arrieta's mechanical problems were worse from the stretch, which helped create those awful strand rates. OPS with men on base in 2012 is was 150 points worse than with the bases empty, and in his Orioles portion of 2013, it was 200 points worse.

In 2011 it wasn't as bad, and in 2010 he actually pitched much better with men on. So, probably I'm making something out of nothing. But it did seem like his work from the stretch was particularly bad, I wonder how one separates that from just pitching badly when things are going badly (which puts you in the stretch more often.)

I always liked him; it is bittersweet to see him succeed elsewhere.
These articles are great. The only issue is that it clearly takes considerable time to put together the comprehensive argument, but there are so many players who I'd like to see evaluated in this way.
Thanks, David. I'm glad you're enjoying the column. If there are any particular guys you'd like to see profiled next week, be sure to let me know.
Man, there are so many potential options. Off the top of my head...
Does Porcello's ground ball tendencies and relative youth make him a worth another chance?
Will Votto's power come back and make him a buy low candidate?
Is Brantley legit or should we sell high?
Is Alfredo Simon waiting for a second half correction or is he legit? Also, can we use him as a model for relievers who successfully transition to the starting rotation.

I can't imagine you'll never run out of players.
Agree with David, these are great. Selfish me wishes they were daily or a few per week! I know he hasn't pitched many MLB innings, but how about maybe Jesse Hahn for a future article?
As an Ubaldo Jimenez owner, I see some similarities to him last year. Last year in the second half Jimenez was terrific and there was an article about how he may have found more consistent mechanics and so could be set to realize his potential once again. Interesting that Ubaldo is now in Baltimore and has not been good.