Corn on the Cobb | The Process Report

Corn on the Cobb

Alex Cobb was a staple in the Rays rotation from 2011 to 2014. He was the Rays most consistent starter through the 2013 and 2014 seasons, combining for a 2.82 ERA in 49 starts between those two seasons. Cobb even took the mound in the 2013 Wild Card Game in Cleveland. He came into the 2015 season as the Opening Day starter, however, some arm discomfort in late spring eventually led to Tommy John surgery that May.

Up to that point, Cobb made a living with his sharp split-change and curveball. The splitter was as unhittable as can be. Cobb was able to induce weak contact, or he simply just got hitters to chase.

Example below:

That’s always been his go-to pitch. It’s easy to see why. The amount of drop that the splitter has pre-TJ was incredible. It wasn’t fun to try to hit, and it certainly didn’t help that his pitches managed to drop so sharply *that* close to the plate. Digging into some ’13 and ’14 numbers, you can quickly get a feel as to how much Cobb really made guys chase pitches.

Season Team O-Swing% Z-Swing% Swing% O-Contact% Z-Contact% Contact% Zone% F-Strike% SwStr%
2013 Rays 32.6% 60.0% 44.7% 66.4% 87.5% 78.9% 44.1% 59.3% 9.4%
2014 Rays 36.3% 61.6% 45.6% 64.6% 89.0% 76.7% 36.7% 59.3% 10.6%

Including his fastball and curveball along with his splitter of course, Cobb was able to post an O-Swing% of 32.6% in ’13, and his O-Swing% sat at 36.3% in 2014. This speaks to the effectiveness that Cobb carried over those two seasons in particular. While not exactly overpowering anyone with his fastball that mostly sits in the low 90s, he was able to find his groove with the offspeed pitches that he threw.

However, 2015 happened. Tommy John surgery came and went for Alex Cobb, and a lengthy rehab followed. We’ve all heard the stories of how difficult TJ comebacks are, and for someone who doesn’t hard like Cobb, it’s easy to feel a little anxious. The questions that followed that surgery ranged from whether his velocity would come back (and he needs all of it), to how much the procedure would affect the spin and dive on his splitter.

Since his return from TJ, Cobb has pitched to the tune of a 6.35 ERA over 51 innings while allowing 70 (!!) hits. While he’s shown flashes of being the old Alex Cobb, there have been some worrying trends as of late. We can start off with the splitter. It’s like a disappearing act, honestly. It’s there sometimes, and then it isn’t.

That split there was flat, and it hung up right in the zone. Machado lined that pitch to LF for a basehit, and he stung it pretty hard at 111.6 MPH off the bat.  One of the main strengths behind Cobb’s splitter is the lack of velocity on batted balls, and it’s pretty concerning when his bread and butter is not only flat, but being butchered for base hits.

Looking a little deeper into Cobb’s batted ball profile for the ’16 and ’17 seasons, you can clearly see the difference in effectiveness overall.

Season Team O-Swing% Z-Swing% Swing% O-Contact% Z-Contact% Contact% Zone% F-Strike% SwStr%
2016 Rays 33.2% 65.6% 46.1% 77.9% 88.1% 83.7% 39.9% 65.4% 7.5%
2017 Rays 30.9% 66.5% 47.4% 63.8% 92.0% 82.1% 46.4% 65.1% 8.5%

Z-Swing% is the one that gives you a very good read on what’s been going on with Cobb. Hitters were simply chasing his pitches out of the zone in previous seasons, which is why his Z-Swing% was sitting comfortably around the 60% area from 2011-2014. The lack of finish/break on his pitches now limits the amount of chases that Cobb himself induces. Flat splitters that hang up in the zone are going to be swung at, as opposed to the full on splitter that does its job and ends up diving down and takes hitters out of the zone.

But sometimes, Cobb unfurls this beauty:

That is the split-change that we’ve all come to know. But, what contributes to this disappearing act? There’s a very noticeable difference between the split he threw to Machado above, and the split he threw here to Castillo. You can see the action, and the unreal late break that Cobb got on that pitch. The fact that he also throwing his original split at times makes you wonder if this has nothing to do with TJ, but rather with the fact that Cobb missed lots and lots of time and that it’ll take constant repetition to get that muscle memory down again.

The usage of the split has dropped from 37.16% in 2014, all the way down to 23% this year. That drop in the split obviously means that the usage rate has increased for another pitch. That pitch happens to be the curveball. He’s thrown it 34.78% of the time here in April. That brings me to my main point here. Can Cobb lean on his curveball while he brings his splitter back into groove?

Typically, starters are supposed to have 2 other pitches at best, to compliment their fastball. If you throw two pitches as a starter, then you better have some electric stuff. Chris Archer comes to mind as a guy who thrives with only his fastball and his slider, although he’s had a changeup that he really hasn’t thrown much up until this season.

However, I strongly believe that Cobb can make it work. He has a plus curveball, and that’s evidenced here on a pitch to Welington Castillo. His curveball is of the knuckle-curve variety.

He’s not afraid to throw it either, as he doubles and triples up on it numerous times. So it’s easy to see how Cobb can lean on his curveball for time being while he works his splitter back. Knowing how much I love spin rates, I used the always reliable Baseball Savant and pulled up what Cobb’s knuckle-curve looks like. Cobb sits 17th out of 43 within those who throw knuckle-curves with a spin rate of 2547 RPM. McCullers’ world class curve sits 3rd with 2843 RPM, for some reference. Cobb is managing to suppress hitters at the plate with his curve. He’s holding guys to a .353 SLG%  For Cobb, however, the spin is there and so is the break. It isn’t difficult to imagine Alex finding some sort of success for the time being with his curveball as his go-to.

Coming back 100% after a surgery like Tommy John is far from a guarantee. It takes time, patience, and lots of repetition. It might take Cobb all of 2017 to find his groove, but then again it could happen in his next start. The best thing we can hope for as fans of the Rays is that he keeps getting his chances to start and build off every outing. That old Alex Cobb is in there somewhere.