Just How Good Is Alex Cobb?

Before the line drive that sent his season to a screeching halt, Alex Cobb was pitching the best baseball of his entire career. In his first 13 starts of the sseason, Cobb went 6-2 with a 3.01 ERA, managing an 8.2 K/9, a 2.5 BB/9, and a 58.3% groundball rate in 83.2 innings pitched. Cobb was never touted to be a frontline pitcher, but that’s exactly what he was looking like at the beginning of the year. Then the injury happened and we were not sure what to expect when Cobb came back two months later. As it turned out, not much has changed. Before the injury, Cobb had a 3.01 ERA. In his 5 starts and 30.2 innings pitched since he returned, Cobb’s ERA has actually been a shade better at 2.93. Despite the liner that derailed him for so long, Alex Cobb has seemingly made 2013 his coming-out party, morphing into an ace-type pitcher before our very eyes. Can this dominance that Cobb has found extend to next season and beyond?

Since Cobb has returned, his ERA has been excellent, but his peripheral statistics have not been as encouraging. Cobb’s strikeout rate has stayed right at 8.2 per 9 innings, but his walk rate has skyrocketed to 4.1 per 9. His homer rate has gone up just slightly, from 1.0 per 9 to 1.2, but his groundball rate has dipped from 58.3% down to 50.6%. Is the league starting to figure out Alex Cobb? Is his feel good story of a season about to unravel?

Comparing Cobb’s Pitch F/X data from Brooks Baseball from before and after he got injured, the good news is how good his curveball has been. Since even before the season, the Rays have been raving about how far Cobb’s curve has come, and lately it has been especially excellent. Before the injury, he was throwing it for a strike 56% of the time, forcing a swing-and-miss 6.3% of the time, and forcing an 8.25-to-1 groundball to flyball ratio. Since then, his groundball to flyball ratio has dropped to a much more reasonable 2.25-to-1, but he has thrown it for a strike 62% of the time and forcing a 14% whiff rate. Cobb always had that big slurvy curveball. Now it’s becoming a real put-away pitch and makes his overall profile as a pitcher look even better. If you take out the bizarre game where Cobb struck out 13 batters in just 4.2 innings, his K/9 in his first 13 starts drops to 7.2. Now, without any crazy games, he’s striking out just as many batters thanks to his curveball. This could be a real breakthrough–maybe Cobb worked on his curveball during his rehab–or just five good games. Either way, seeing Cobb’s curveball work this well bodes well for his future. His issue, though, has been his sinker.

The league average swing-and-miss rate for sinkers is 4.6%. In his first 13 starts, Cobb was a touch below that at 4.2%. But Cobb has never needed his sinker to be a swing-and-miss pitch–that task he always left to his split-change. The critical thing was that he threw it for a strike 66% of the time and forced a solid 1.75-to-1 groundball to flyball ratio. Since coming off the DL, though, Cobb’s fastball just hasn’t been there. His whiff rate on it has dropped to just 2.2%, and while his strike percentage had stayed right about where it was at 64%, his groundball to flyball ratio has fallen to just 1.10-to-1. Cobb’s sinker always forced groundballs and the occasional swing-and-miss despite staying in the 90 to 91 MPH range. Lately, that has not been the case at all. Did the league adjust to Cobb’s sinker? That’s a possibility, but maybe he just isn’t commanding it well. Will the command come back? Normally, we would have to say yes, but this case is a little more complicated. Cobb is coming back from fluid buildup in his ear, something that could severely hurt his balance, and possibly mess up his command. Hopefully this is just five bad starts for Cobb’s fastball command and everything will be fine. But if Cobb is truly taking the next srtep as a pitcher, his sinker command has to be pinpoint or hitters will get to him. And combining the command factor with the chance that the league will indeed adjust to him makes Cobb future look significantly bleaker than before.

What will Alex Cobb give the Rays for the remainder of this season and beyond? We honestly don’t know. After the injury and the way his performance has fluctutated, we can’t be sure exactly who he is as a pitcher. But there is one thing we do know: behind David Price, he’s the most dependable pitcher the Rays have right now. James Shields is gone, and Alex Cobb has replaced him as the Rays workhorse. Is Cobb emulating what Shields was in his last two years with the Rays, a second ace along with Price? Will Cobb slip back like Shields did for a time, leaving his future in question? The coming seasons will tell the story. However, turning a pitcher who wasn’t the most highly-touted in the prospect into a pitcher as good as Cobb has been is already quite an accomplishment. If Cobb does take that next step as a pitcher, it will just be icing on the cake.