Josh Reddick vs. Pitch Speed

After the 2012 season, I wrote this article about Josh Reddick. Basically the gist of it is that despite having a breakout year, Reddick has a swing flaw that limits him against fastballs. Then last year I discovered Athletics Nation and wrote this piece basically saying the same swing flaw is still there and again he will struggle with fastballs (which he did, -3.6 runs below average according to Fangraphs). So for this year I am getting my Reddick vs. Fastballs piece done early.

With the season starting to draw near, I started thinking that maybe Reddick could be platooned. Not in the traditional righty/lefty sense (in which Reddick is virtually the same) but maybe against certain pitchers. So I did a study on how Reddick performs against pitch speed. The website BaseballSavant.com allowed me to look at pitches Reddick sees for any velocity based on PITCHf/x data. I looked at pitches Reddick saw in the strike zone and tracked what percentage of these pitches he got hits.

Of course there are some limitations to this study. First, I only collected hit percentage. I didn't calculate SLG or anything like that. Second, Reddick didn't swing at every pitch in the strike zone (taking the first pitch, etc.). But I just figured it would even out across all pitch speeds and moved on (if anything, it seems like he would swing at more fastballs in the zone than anything else). Last, the higher velocity stuff is subject to sample size. But overall good enough for a Friday read.

Let's take a look at the data.

Interesting. Reddick's overall Hit% on balls in the strike zone is 9.4%. We see the trend has a somewhat predictable profile. The Hit% goes up as we include pitches with higher velocity (higher percentage of fastballs included, lower percentage of breaking balls) then falls off at a certain velocity - the velocity Reddick can't handle. Unfortunately, that velocity is pretty low - 88 mph. Every mph over 86 a pitcher can throw, the likelihood of Reddick getting a hit on a pitch in the strike zone goes down. If the pitcher can throw up to 94 mph, Reddick is 10% less likely to get a hit than off someone who only throws up to 88 mph.

If you have read the articles referenced above, you know that Reddick has some issues with his rear arm function. So I thought I would compare him to someone who has really good rear arm function - Andrew McCutchen. I repeated the same analysis for him and here is his profile.

McCutchen's profile is very different. It is nearly flat across all pitch speeds. A pitcher can throw as hard as he wants, it really doesn't matter. Unlike Reddick, McCutchen's likelihood of getting a hit is really independent of how hard a pitcher throws. That's awesome! (If you are wondering I didn't run the numbers on Donaldson. Really only 1 season's worth of data.)

Going back to Reddick's numbers again, we can see he really doesn't like the heat. Past 90 mph, Reddick really tails off. At 94+, he has a pretty hard time making contact much less getting a hit.

So what does this mean? Maybe Reddick's days off can coincide with days the opposing pitcher can really bring it. Or maybe he should be hit for late in games if the closer throws triple digits (of course Oakland loses his defense then). Or maybe for goodness' sake he should fix his rear arm's movement in his swing!