Is Alex Cobb the Answer?


We’re only a few days away from the MLB Trade Deadline and the Rays are evaluating their options. A player who could be important in the Rays’ decision-making process is Alex Cobb. Is Cobb going to be traded? Almost assuredly no. But the question the Rays are asking themselves is whether their starting rotation is good enough to allow them to keep contending even if they trade James Shields. The Rays have to be evaluating whether Cobb, Chris Archer, and Jeff Niemann, who is getting ready to begin his rehab from his fractured leg, are capable enough to fill the final two spots in their rotation. This is a big time for Cobb and who knows how important his start tonight will be in the Rays’ decision-making process about whether to trade Shields. But let’s ask the question ourselves: is Alex Cobb a good enough pitcher to be a starter on a team with so much pitching depth and that is so heavily dependent on its pitching staff?

Cobb’s numbers this season have not been pretty. He has gone 4-7 with a 5.05 ERA in 11 starts and 62.1 IP. However, his peripherals have been much better. He has struck out 6.6 batters per 9 innings while walking 3.3 and he has allowed just 0.4 home runs per 9. His groundball rate is a great 60.0%. The results of all that is that Cobb’s FIP has been 3.51, his xFIP 3.76, and his SIERA has been 3.79. Cobb’s FIP, xFIP, and SIERA in 2012 are actually all better than 2011. So why is there such a high discrepancy between Cobb’s ERA in 2012 and his FIP? The clear answer is that Cobb picked the wrong year to post such a great groundball rate with the Rays’ infield defense the worst it has ever been since the Devil Rays days. But could there be something going on more than that? Let’s look at what’s really going to make our break Cobb, not his stats, but his pitches themselves, and analyze just how good he really is. The data is courtesy of Brooks Baseball and it is graphed in my original display. For the maximum sample size, we’ll use his data both from 2011 and 2012.

As we see in the key, Cobb and Shields have one big thing in common: their dependence on their changeups, with Cobb’s being of the unique split-change variety. But unlike Shields, Cobb throws his split-change less than his fastball and sinker, which might as well be grouped together because they’re very similar pitches (I’ll keep them apart on the graph because Cobb tinkers with his release a little bit on the sinker). Cobb really doesn’t throw very hard and doesn’t force a lot of swings and misses. What swings and misses he does force come on his dynamic split-change. According to Brooks Baseball, Cobb’s split-change has accounted for an insane 72% of his swings-and-misses over the past two years. It really is a great pitch, but it wouldn’t be as effective if Cobb used it much more than he does. Luckily, he’s able to do that thanks to his other pitches. Cobb’s fastballs don’t have much velocity and don’t have too much late life, but they feature nice sink and are effective groundball pitches that Cobb isn’t afraid to throw. Cobb’s curveball features more big depth than sharp break, but it too is an outstCanding groundball pitch. Cobb’s overall control is good, not great, but he keeps the ball down and makes a living off of forcing groundballs. Unfortunately for Cobb, his defense has let him down and that has gotten him into trouble. But Cobb has a good enough arsenal to succeed as long as his defense does its job, and while Cobb isn’t going to blow you away, he has the ability to be a perfectly fine big league fourth starter.

The Rays aren’t going to suddenly give up on Alex Cobb. We haven’t heard any rumblings about the Rays even considering removing him from the rotation. Cobb has pitched fine this season and has simply been the recipient of bad luck because the defense behind has collapsed. Cobb is no star, but he has the ability to be a cheap, dependable option for the Rays at the back of their rotation for the next several years, and with better defense, he could thrive in that role.