Alex Cobb’s Pitching Adjustments

As most of you already know Alex Cobb is a pitcher for the Tampa Bay Rays. He is projected to be their “ace” in the upcoming season. In fact many people would argue that he’s the best pitcher in the AL East. Considering Masahiro Tanaka’s health issues it doesn’t seem unreasonable to assume that this might be true. Cobb, however, wasn’t always considered a top of the rotation starter. Since arriving to the majors, Cobb has made significant adjustments to his pitching style, which has earned him his current reputation.

The Rays drafted Cobb in the 3rd round in the 2006 Major League draft. After spending a few years in the minors, in 2011, Cobb made his Major League debut. He pitched 52.2 innings that year and finished with a relatively good ERA, 3.42. 2012, was essentially his first real full season in the big leagues and he didn’t do so well. Cobb, that year finished with a 4.03 ERA. His peripheral numbers, however, were relatively good, his FIP being 3.67 and his xFIP being 3.54.

The next two years Cobb became an extremely dominant pitcher. In 2013, he finished with the best ERA of his career at 2.76 and in 2014 his ERA was only slightly worse at 2.87, but still stellar. His FIP and xFIP, however, have remained consistently in the mid to low 3s. Over the past two years mostly in the low 3s. Many of us have a good understanding of FIP and understand that Cobb’s recent ERA production may just be a normalization of FIP. This may very well be true and an important element to consider, however Cobb in the past two years Cobb has made significant pitching adjustments, which may indicate that this recent ERA success is no fluke.

So what type of adjustments has Cobb made? Well thanks to Brooks Baseball PITCHf/x tool we have a sample size of Cobb’s pitch usage leading back to 2010. If you look at the graph below one thing truly stands out in Cobb’s pitch mix.

 

Cobb as you can see in the graph above has four essential pitches. What is most notable is how Cobb has made use of his fastball and sinker or inverted their use. In 2010 his fastball was one of the pitches he used the most. In 2013, however, he made a significant decision to use the fastball a lot less. It’s actually the pitch he’s started using the least. Cobb now mostly throws his off-speed pitches and his sinker. The sinker now is basically the pitch he’s using most frequently. Both pitches are predominantly thrown at the same speed, around 92 mph according to Brooks Baseball. The biggest difference is that the sinker has more movement or vertical movement while the fourseam fastball does not.

In the chart below is an example of the vertical movement on Cobb’s pitches. Why vertical movement? Because Cobb throws a splitter, a curveball, and a sinker, which are all conducive to vertical movement.

 

The sinker or movement on a sinker can be more favorable in creating a higher groundball percentage. It, however, has not been the case with Cobb; his groundball percentage has always remained around his career average of 56.5%. One of the more drastic differences in Cobb’s results in correlation with his new pitching technique is his whiffs per swing.

As you can see here, at the same time that Cobb started to decrease his use of fastballs, he started getting more and more swings and misses with the pitch. The splitter and the curveball have also been pitches which have induced more swing and misses due to his new pitch mix. What one can primarily take away from this chart is that hitters now seem to either be sitting on his sinker or sitting on a pitch with movement (the sinker would fall into that category). Cobb’s fourseam fastball is really the only pitch that doesn’t have significant movement and yet it’s getting a ton of swing and misses even though it’s being thrown a lot less. Meaning that hitters are probably expecting a pitch with movement and when the fastball is thrown they are either surprised or not prepared to hit the pitch.

Cobb here has transformed one of his weakest pitches into one of his strongest. Many young pitchers, and veterans for that matter rely a ton on their fastballs, yet it might be a drastic mistake. If you don’t have an overpowering fastball, like Cobb’s, a good pitching strategy could be to stop throwing it very often. There is no one way to pitch, just like there is no one way to get wins or be successful. Most pitchers are taught at an early age that everything derives off their fastball; “you need to establish your fastball early in the count to set up your off-speed pitches”. This is not true; if you want you can throw off-speed pitches early and then throw fastballs or not throw fastballs at all. There are no rules to dictate the way one pitches and Cobb is exploiting that.

Cobb’s success can serve as a template for younger pitchers, in the minors or majors who do not throw 95+ mph and are trying to compete in this hard-throwing era. It actually can also serve as a formula for pitchers who are getting older and are losing their fastball velocity. Cobb is a very good and unique pitcher, and should be someone who pitchers try and emulate.