2012 proved to be quite the momentous year for Johan Santana. After missing the entire 2011 season following major shoulder surgery, the 33-year-old Venezuelan silenced critics with 5 shutout innings (and a no-decision) on Opening Day. While it wasn't a dominant start, El Gocho showed us that his stuff is effective at any velocity (his fastball in 2012 averaged 88.4mph, down from 89.6 in 2010) as he struck out five batters and escaped a bases-loaded, no-out jam in the fifth inning.
In fact, Santana looked every bit the part of the ace the Mets lacked, averaging better than 6 innings per start and a 2.39 ERA through his first eleven starts. His eleventh start last year was especially significant. I don't want to be the one to tell you what happened, so I'll let Gary Cohen tell you here.
What immediately followed is, well, not so good. What you often hear is that Santana, well, stunk after that night. In the 10 starts that followed, Santana averaged under 5 innings / start and posted a Oliver Perez-esque 8.27 ERA. Because of this, the common theme is that Santana is now a question mark for 2013. But is he?
Let's look at some numbers [Note: "Pre" references starts up to and including June 1st, "Post" is everything after]
K/9, BB/9, K/BB, BABIP
Pre: 9.0, 2.78, 3.24, .259
Post: 7.90, 3.31, 2.39, .357
The biggest thing to note is that Santana's walk rate jumped 19%. The strikeout rate dropped 12% as well, but the 7.90/9 exactly matches his rate in 2009/10, so it isn't exactly a red flag. The most significant thing to note is the major increase in BABIP. Some of that is indicative of his struggles, but some does indicate some unfortunate regression (his career BABIP is .276). The numbers here do indeed indicate a major regression in his performance, but blanket statements here may be misleading.
What is seemingly overlooked in analyzing his decline is the major ankle injury Santana suffered against Chicago on July 6th. I posit that this be used as the 'turning point' in Santana's season, and here's why (on a start by start basis):
June 8th, @NYY: 5IP, 7H, 6ER, 1BB, 5K
Santana certainly struggled against the Yankees here, but it was almost a perfect storm of factors that led to this. First, Johan was given an extra 2 days of rest which some argue threw off his schedule. Second (and perhaps, more importantly): Santana, who has always been a fly-ball pitcher (his career Ground-Ball rate is only 37.2%), started a game in a notorious home-run hitters' park, against a notorious home-run hitting team (the Yankees hit 245 home runs, breaking their own franchise record and totaling the 7th most all-time). Of the 10 balls put in play against Santana that day, 6 were hit in the air. 4 of them left the park.
June 14th, @TBR: 5IP, 6H, 4ER, 4BB, 6K
A sloppy start for Santana, in which he allowed 10 baserunners in 5 innings. That said, he did keep the ball in the yard. He did allow 1 fewer hit, and struck out an additional batter, but he walked three more than in his previous start. In all, an improvement. This wasn't a 'quality' start by any means, it is at least passable.
June 19, vs. BAL: 6IP, 4H, 0ER, 2BB, 5K
This was Santana's first 'good' start after the no hitter, and it came against a quality Balitmore Orioles team. He seemed to shake off his funk here, and it showed in his next few starts.
June 25, @CHC: 6IP, 5H, 2ER, 3BB, 6K
Santana has thrown back-to-back quality starts, and seems to be getting back to where he was. His control was a bit shaky, giving up three walks, but he continued to have a good strikeout rate (22K in 22IP in these four starts, matching his pre-no-hitter rate), but the walks were definitely up (10BB/22IP).
June 30, @LAD: 8IP, 3H, 0ER, 2BB, 3K
Not many strikeouts in this start, but very effective nonetheless. In fairness, it was against a depleted Dodgers lineup, but for Santana to go beyond 6 innings for the first time in a month was a good step forward. He was also much more efficient in this start, averaging just over 13 pitches per inning. He may not have been dominant (if you consider the low strikeout total) but he was about as close as it gets.
At this point, we can see that Santana was not nearly as bad after the no-hitter as we get told, he was still pretty good. His ERA in these five starts was 3.60 (12ER/30IP). Not great, but certainly respectable for someone supposedly 'worn out' following a 134-pitch no hitter following anterior capsule surgery (if you remove the start against the Yankees, his ERA in the other four was a paltry 2.19). His In his next start (vs. CHC), he started out fine (2ER in the first 4 innings, before having his ankle injured covering first base on a Reed Johnson groundout). After that moment, things turned for the much-much-much worse. In the 15 innings Santana would pitch following the injury, he gave up a total of 31(!) earned runs.
Now, this is no guarantee that Santana will be in vintage form next year. What it is, however, is a theory - one at least as credible as any other - that Santana's ankle was the reason behind his decline. His shoulder, in the meantime, seemingly showed no long-term fatigue. Johan Santana can be fairly considered a variable going into next season. But he's a gamer, and has shown that he can work effectively with what he has. And many of us said these things a year ago. After seeing Santana pitch opening day this year, I'm willing to put my money on him going forward.