Right now, Johan Santana looks as if he’s having a fantastic year on the surface, but signs are pointing to a harsh decline. High contact rates and low groundball rates are recipes for disaster, and that’s what Santana’s stuff is generating right now.Since Jack Moore wrote that article back on June 11, Santana has definitively displayed a good deal of the regression that Moore predicted. In four starts, Santana has allowed 14 ER in 26 IP for a poor 4.85 ERA with a 1.346 WHIP. His BABIP has jumped from .268 to .284 and his ERA is much closer to his FIP now than it was then.
However, while I think there is a good possibility that Santana is not going to pitch like the ace pitcher he once was, I also believe that Moore's prediction of a "harsh decline" is, well, harsh, for a few reasons:
1) Santana never was a fastball pitcher. The fact that Santana's average fastball velocity is down to 89.3 MPH this year concerns me, without a doubt. But Santana's bread and butter has always been that change of his, and the speed difference between his fastball and change is still a strong 10 MPH. The combination of the pitch speed difference and Santana's willingness to use that change at any point during an AB tells me that he still has enough stuff to be strong when he's on his game.
2) Santana has always had a high strand rate. Santana's 75.1% strand rate this year is 3.1% above league average, but still puts him only 39th among qualifiers...hardly a red flag. Furthermore, his number this year is below his career rate of 77.2%. I'm reluctant to automatically conclude that Santana "knows how to get people out" or some such irrelevant nonsense, but Santana is one of those pitchers whose strand rate has always been better than average throughout his career. The result, typically, is a better-than-expected ERA based off of his FIP.
3) Santana has always been a high-HR pitcher. Even during his peak, Santana was always a 20-25 HR hitter per year. He's always been a flyball pitcher, and while his G/F has been extreme this year, I expect that to normalize over time. I agree with Moore that Santana is due to give up more HR, but don't see this as a deal breaker based on his profile.
4) Citi Field isn't going to start playing differently. The jury is still out on whether or not Citi Field suppresses HR (it is next to last in the Majors this year in HR but was middle-of-the-pack last year) but it definitely has been a pitcher's park in terms of run prevention. Santana's ERA is lower on the road (3.17) than at home (3.68) despite only one HR allowed at Citi Field all year. You could argue that Santana is due some better luck at home and that his home ERA should drop based on the law of averages.
I don't want to oversell this premise. I agree with Moore that Santana isn't the same pitcher he was with the Twins because - simply put - he isn't. He whiffed over a batter an inning from 2002-2007 in Minnesota but hasn't even cracked eight per nine in New York. I'd go a step further than Moore. In retrospect, Santana declined in 2008 and hasn't bounced back to his peak. He's a good to very good pitcher, but if you paid him ace money this spring in hopes of a bounce back to 2007 or earlier, you're almost definitely going to be disappointed.