Adjusting to Josh Hamilton

The easy thing is talking about what Josh Hamilton has done. For his career, he’s hit .304, with 161 dingers. Last year, his WAR was 4.4, and before that it was 4.1, and before that he won the American League MVP. Hamilton just signed a substantial contract with the Angels, and the season most relevant to the Angels during negotiations would’ve been Hamilton’s 2012. Hamilton started impossibly strong and cooled off, finishing with excellent numbers overall. If the Angels didn’t think Josh Hamilton is excellent, they wouldn’t have guaranteed him an eighth of a billion dollars.

The harder thing is talking about what Josh Hamilton will do, precisely because we don’t and can’t know. We can only try to guess, based on what we assume to be relevant information, and when talking about Hamilton’s future — which everybody’s tried to do — it seems worthwhile to take a closer look at those 2012 trends. For some time, Hamilton was practically impossible to pitch to. Then he became easy to pitch to, at least relative to the earlier version of himself. Random statistical fluctuation, or something the Angels ought to be thinking about?

It can be sloppy to divide a season at an arbitrary date, but it’s also extremely simple and you can still get a point across, if there’s a point to be made. Through the end of last May, Josh Hamilton had a 1.184 OPS. He struck out in 19% of his plate appearances. Over the remainder of the season, Hamilton posted an .809 OPS, and he struck out in 29% of his plate appearances. Hamilton started off as the greatest player in the world, and he finished getting booed by his own hometown fans as the Rangers somehow missed the playoffs. One wonders what might have changed. There’s not always something that changes when numbers behave in this way, but it’s not a bad idea to check.

I wondered how pitchers might have adjusted their approaches to Hamilton after Hamilton demonstrated that he could just hit dingers whenever he wanted to. See, a neat thing about pitching is you’re not locked into a concrete game plan. You can make changes, in anticipation or even on the fly. Given what Hamilton was doing toward the start last year, it would make sense if pitchers and catchers gave their plans a second thought. To examine, we turn first to the plate-discipline data:

We don’t see anything in the first three columns of data. Pitchers threw roughly as many pitches in the strike zone, and Hamilton was swinging at the same locations, more or less. The last two columns are more interesting — Hamilton made less-frequent contact. At strikes and at balls. When it comes to investigating pitcher tendencies, what’s simpler than looking at raw fastball rate? Was Hamilton seeing fewer fastballs over the course of the year? Presented below is a graph, showing Hamilton’s rolling average fastball rate, based on 20-game samples:

That’s not necessarily very helpful, as we can identify relative maximums and relative minimums. But there does seem to be the hint of an overall drop as you move along the x-axis (Time). Hamilton’s fastball rate was already low; it only got lower. Let’s break this data down by handedness.

Against righties, Hamilton saw a reduced fastball rate, and an increased whiff rate. Fewer of his swings resulted in batted balls put in play (or hit for dingers).

Similar against lefties — fewer fastballs, more whiffs. The samples are smaller, of course, but still in the hundreds of pitches. Overall, combining righties and lefties, Hamilton’s rate of fastballs seen dropped from 53% to just under 49%. That’s small, and it might just be a consequence of Hamilton getting into more deep and/or pitcher-friendly counts, but it could be meaningful. It would help to have the Rangers’ overall rates of fastballs seen, for the sake of comparison.

There’s something else we can look at pretty easily, and it’s first pitches. Hamilton is a free swinger, and he’s not afraid to go after the first pitch of an at-bat. Against righties, Hamilton’s first-pitch fastball rate dropped from 60% to 52% after May. Against lefties, it dropped from 60% to 47% after May. These differences feel more substantial, and suggest that pitchers were trying to counter Hamilton’s aggressiveness. Interestingly, against lefties, Hamilton’s first-pitch swing rate dropped from 68% to 49% after May. The samples are limited, but Hamilton calmed himself down.

The data indicates that Josh Hamilton saw fewer fastballs last season after his torrid stretch of productivity. That should hardly come as a surprise, yet Hamilton’s initial fastball rate was already very low. Overall, Hamilton saw 50% fastballs. Out of 1,685 player seasons since 2002, Hamilton in 2012 had the sixth-lowest fastball rate. The lowest we’ve measured is 47%, for 2009 Ryan Howard. Hamilton was near an extreme.

Hamilton saw fewer fastballs, and fewer first-pitch fastballs, and his numbers got worse and his strikeouts went up. It will be interesting to see if this continues, to see if Hamilton sees even fewer fastballs still going forward. In that event, it will be interesting to see how Hamilton responds, to see if he can deal with it and continue to produce at a high level like the Angels expect. Last season, Hamilton didn’t stop swinging, and he missed more and more. If pitchers are aware of that, then it’s Hamilton who’s going to have to make the adjustments. The Angels, clearly, figure he’ll be fine. And, maybe, he will be.