A Grand New Year

Before the witchcraft of Kevin Long, Granderson looked like this:

This graph visualizes how Granderson performed based on pitch location using linear weights. This graph only shows area inside the strikezone, which is sliced into 16 squares. Blue is good for Granderson, Red is bad. The graph is from the catcher’s perspective, so the right side of the graph is close to Granderson and the left side is away from Granderson.  You can enlarge the graph (and all following graphs) by clicking on it. Unsurprisingly, Granderson was good when he got a pitch on the inner part of the plate. He was bad basically everywhere else. If you were to throw a pitch to Granderson anywhere except for the inner part of the plate, you would expect a negative outcome for Granderson. After the witchcraft of Kevin Long, Granderson performed like this:

As the above chart shows, Granderson improved everywhere. He still struggled on pitches down and away from him, but that’s normal for left handed batters. What’s important is that 3/4 of the graph is no longer an area of poor performance for Granderson. Looking at these two graphs, it’s pretty clear that Granderson was able to fix some of the holes in his swing. This seems to support my theory. His swing was clearly different, so it would make sense that a change in his batted ball profile would follow. Now to the meat of my theory. If correct, there should have been an improvement in Granderson’s ability to drive baseballs to the opposite field after the swing change. The following graph is the result of this research:

This graph shows Granderson’s performance (according to linear weights) based on the angle he hit the ball (pull, oppo, etc.). The right side of the graph is right field, the middle of the graph represents center field, and the left side of the graph shows left field. The green line depicts his performance prior to the swing change, and the black line shows his performance following the swing change. Turns out that my theory was……completely wrong! He performed almost exactly the same on balls hit to the opposite field during both time periods. The swing change did alter his batted ball profile…by making him better at pulling the ball than he already was. Caveat:  It is important to understand that this is the conclusion merely suggested by this data. It is still possible that he improves on pitches hit to the opposite field. These sample sizes were pretty small, so in order to evaluate his swing change in a completely conclusive manner, we will have to wait for more data.

*Graphs were constructed using the pitch f/x data from Darrel Zimmerman’s pbp2 database.
*PITCHf/x data from Sportvision and MLBAM.

One thought on “A Grand New Year

  1. JoshWeinstock

    Yea, Granderson is somewhat similar to the league average lefty. The bump is mainly because of more homeruns into the short porch (on a rate basis of course).

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