During a recent game, pmayo noticed Ryan Theriot had learned to turn on the inside pitch, and opponents were paying the price. After running the numbers, I had confirmed* it.
*I realize batted ball direction matters, so that's an overstated conclusion
By cutting all pitches seen by Theriot by "slice", you can see the changes from year-to-year. Click for a large version:
- For the most part, Theriot is swinging a little more. He already had a lower than average swing rate, so he certainly had room to go up. He hasn't increased his swing rate on Tight pitches, but that's the slice that gets the fewest pitches, giving it little weight.
- Theriot is also whiffing more, except on "In" pitches. Theriot has always carried a low whiff rate, so this is noticeable (small sample size warning).
- Power. Theriot has found a little bit of it, especially middle-in.
Here's a breakdown of Theriot's "in" slice. That covers the inner 3.5 inches of the plate, and 3.5 inches off the plate.
year # nkSLG Swing Whiff
2007 202 0.231 0.564 0.070
2008 427 0.358 0.466 0.050
2009 86 0.677 0.535 0.044
And, by year, plate locations for doubles and home runs: