What Should We Expect From Glen Perkins on Wednesday?

Before I begin this post, I’d like to preface it by saying that trying to predict the events of a single start is pretty dumb. So what am I going to do? Try to predict the events of a single start, of course.

Glen Perkins’s recent history with the Twins has been of bad blood, and bad pitching, but with Kevin Slowey out of Wednesday’s start nursing a sore elbow, the Twins really need their former first round pick to come through in what will be a big start against Chicago.

Perkins main problem over the course of his career is his pitches are all extremely similar to each other.

As this image shows, his fastball and his changeup are very similar in terms of velocity. They have basically the same spin, which is good, but even if you can make them look like the same pitch out of your hand, if they’re basically the same pitch when they get to the plate you’re still going to get hit hard.

Interestingly, over the course of his career Perkins has fared much better vs. RHB than LHB. One reason could be that Perkins varies his pitches much more vs. righties than lefties: vs. lefties he throws almost 70% fastballs with another ~20% being sliders. But against righties, while he throws roughly the same amount of fastballs, he incorporates his changeup much more, which could be the key (although Fangraphs’ pitch values rates it as his worst pitch).

Perkins’s pitches do look a little different (and harder to define) against righties than lefties, as you can see below:

While they don’t look extremely different, baseball is, as they say, a game of inches, and the slightest bit of deception can help. But while that is certainly a factor, perhaps the biggest reasoning for Perkins’s relative success vs. RHBs is his approach:

As you can see, Perkins tends to stay away from lefties, which is interesting given the fact that, although Perkins doesn’t have the best fastball, he should still be able to get inside.

Compare it to vs. righties:

Why Perkins uses the full strikezone vs. righties more than lefties doesn’t really make any sense to me, but it is clear that using the whole zone works better for him, as it probably should for any major league pitcher.

The White Sox will likely trot out a lineup consisting of 6 righties (assuming Ozzie starts Andruw Jones over the lefty Mark Kotsay) and a switch hitter against Perkins. But while this would normally be cause for alarm, against Perkins it might not be too bad, as long as you acknowledge the somewhat small sample we have to work with and accept the randomness that goes with it.

I don’t think Glen Perkins will set the world on fire, but a quality start won’t shock me at all.