Can Joba Chamberlain turn around his career?

We've come a long way since the Joba Rules. Joba Chamberlain was once a dominant reliever, giving up a total of two runs during his debut season in 2007 (with a 1221 ERA+), and maintaining a 2.60 ERA the following season, striking out 118 batters in 100.1 innings over 12 starts and 30 relief appearances. However, since the failed attempt to convert him into a full-time starter in 2009, he's been a below-average reliever, save for an injury-shortened 2011 campaign. This season, Chamberlain may be having the worst year of his career, with personal worsts in ERA+, walk rate, and home run rate. Most of us don't expect much from him anymore, but some are still holding out hope that Chamberlain can regain some of his previous form. Here's a detailed look at what he'll need to do in order to reverse this trend, tables courtesy of BrooksBaseball.net.

Trajectory and Movement - from 03/30/2007 to 09/28/2008

Pitch Outcomes - from 03/30/2007 to 09/28/2008

Sabermetric Outcomes - from 03/30/2007 to 09/28/2008

This is the biggest available sample of "Good Joba," from 2007 to 2008. Even if you weren't watching his outings during this time period, it's not hard to tell why he was so good. Chamberlain mixed his pitches well, transforming from a two-pitch reliever in 2007 to mixing in elements of five pitches for most of 2008, and gaining a lot of confidence with his curveball. His setup pitch, the hard fastball, induced a lot more swings than one might expect, but a surprisingly high number of these resulted in fouls or pop-ups. His slider became a dominant out pitch, with a very high whiff rate, and it was complemented well by the emerging curveball, which kept batters swinging at a pitch they couldn't handle. All in all, Chamberlain's stuff was successful in 2007 and 2008, and he maximized the impact of a five-pitch repertoire by relying on two or three strong pitches and occasionally throwing something different to keep hitters guessing. At the time, it seemed like Chamberlain would be a consistent long-term option as either a starter or bullpen ace.

Trajectory and Movement - from 03/01/2009 to 10/31/2011

Pitch Outcomes - from 03/01/2009 to 10/31/2011

Sabermetric Outcomes - from 03/01/2009 to 10/31/2011

From 2009 to 2011 is what I'll call "Intermediate Joba," as his play was typically no better than average during this period, but he still showed signs of his potential. He lost velocity on his fastball and gained some on his curve, but lost some movement on it. Between these time periods, Chamberlain's ability to get called strikes significantly decreased on all pitches (other than the change up, which he had begun to utilize a little more), which suggests that his stuff had become less deceptive, leading to a higher overall line drive rate. Furthermore, and perhaps most ominous, was the fact that his out pitch, the slider, had become much less effective. While the swing rate was stable, largely because he threw it primarily in two-strike counts, batters were whiffing much less often than before, and they had begun to hit the ball in the air rather than on the ground. However, while these issues were troubling, Chamberlain still often flashed his potential enough to not cause too many worries.

Trajectory and Movement - from 03/01/2012 to 08/26/2013

Pitch Outcomes - from 03/01/2012 to 08/26/2013

Sabermetric Outcomes - from 03/01/2012 to 08/26/2013

Over the past two years is where Chamberlain has looked his worst overall. While they're still technically utilized, he's all but abandoned his sinker and change up in favor of his top three pitches. The curveball continued its downward trend, in terms of movement, and, as both it and the fastball became less and less effective, Chamberlain began to throw the slider much more often than before. That pitch, though, was hit in the air just as often as it was hit on the ground, which never bodes well, but especially not for a pitch that, even at its best, was always somewhat susceptible to a home run. And double especially when that pitch is your go-to out pitch when ahead in the count. The ever-increasing line drive rate is probably the biggest reason for his spike in hit rate over the past two seasons, and the weighty home run rate (nearly 1.5 per nine innings) is likely an offshoot of his inability to consistently get strikes when needed.

So what does Chamberlain need to do in order to improve from here on out? To put an entry into the "easier said than done" department, he'll need to keep hitters guessing like he did during his good department. In my mind, that means throwing the slider less and bringing back the change up. While the issue with the slider can be summarized as giving up too much contact, this is most likely a result of hitters predicting the pitch than any change in delivery or pitch directory. With better conditioning, he may be able to regain some some fastball velocity, which would likely increase the effectiveness of his setup pitch that he has seemed to lost confidence in during the past two seasons. It's not as simple as just an adjustment in pitch selection, but I think these tables show trends that suggest where Chamberlain has room for improvement.

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