Anatomy of a player: Jake Peavyby Josh Kalk
March 25, 2008
Jake Peavy is one of the best pitchers in the game. He basically did everything you can ask of a starting pitcher last year. He threw more than 200 innings, he struck out more than one batter per inning, he kept his walk rate incredibly low, and he kept his ERA well below three, checking in at 2.54.
All that added up to a Cy Young for the young right hander. Carlos Gomez broke down Peavy's mechanics last year and explained how the pitcher could be so good with not the best mechanics. Here we will take a look at Peavy's PITCHf/x statistics and see what light those can shed on Peavy's success last year.
Peavy's repertoire contains a mid-90s fastball, a slider, a change-up, and an occasional curve. You might think that Peavy is mostly a two-pitch pitcher, throwing his fastball 58 percent of the time and his slider 35 percent, but as we will see later, that is a bit misleading. Here is a view of these pitches' movement compared to a pitch thrown without spin.
Let's break down these pitches one by one, starting with his fastball. As Carlos showed, Peavy's arm angle is not very over-the-top. This causes his fastball to tail in toward right-handed batters, making it very difficult to track. In fact, his fastball moves almost as much in as it rises, which is very unusual for a pitcher. Tack on the fact he throws the pitch 94 mph and you have a great base to work with.
Peavy's slider, though, is one of the most interesting pitches to look at. The movement here makes it look like this is just one pitch, but I am pretty sure Peavy throws two different sliders, a hard slider and a slider that is more of a slurve. You can really see this when you look at the movement compared to the speed of the pitch.
Here you can see the separation between the two sliders. The hard slider is thrown about 87 mph with much less horizontal movement. The slurve is thrown at about 83 mph with a huge horizontal movement. Unfortunately, my classification algorithm isn't sensitive enough to distinguish between the two. I plan to work during the season on a way to not only say a pitch is a slider, but what kind of slider it is.
I'd love to hear from Padres fans on whether this difference is distinguishable watching the games. How the two sliders affect batters is unknown, but I'd imagine it would be a very hard thing to pick up. In any case, Peavy loves to use his sliders with two strikes and he gets a ton of strikeouts with them.
Peavy's change is somewhat a work in progress. Peavy's horizontal movement is very close to his fastball, but his vertical movement is more than five inches less. He does get almost a 10 mph difference in speeds, which is very solid. Reports say he is working on his change-up during spring training this year, so it will be interesting to see if he stays with the pitch or if he goes back to just throwing it about 5 percent of the time.
Peavy's curve looks a lot like his slurve, but he throws it in the mid-70s instead of the low 80s. Again because of his arm angle, Peavy produces more horizontal movement than vertical movement with his curve, which may be why he is reluctant to use the pitch. When he does use his curve, it almost always is against left-handed batters. Again, this is very likely due to the large horizontal movement of the pitch.
I also want to spend a few minutes on Peavy's release point. I haven't developed all the tools necessary to really do this justice, but Peavy's release point is just too interesting to ignore.
You can see some pitches that weren't properly tracked, but the clump of sliders that is nearly sidearm is real. So if you are a batter and you see him drop down, expect a slider.
Peavy seems to release his breaking pitches at a lower angle than his fastball. This is especially true with his change, which he releases very low. If he is going to use this pitch more, it will be interesting to see if batter can pick up on this different release point.
The other thing to take note of is that Peavy has a very wide release point for a pitcher. Carlos spent a great deal of time discussing this in his article. I don't have much to add except that this, too, must be hard for batters. If a pitcher has very repeatable mechanics, picking up the ball has to be easier. When the release point can change by more than a foot, finding the ball must be hard, to say nothing of determining if it is a fastball or slider.
The fact that Peavy can have such a wide release point and still have pinpoint command is remarkable. If Peavy were walking a bunch of batters you might think about trying to fix that, but why try to fix something that clearly isn't broken?