June 29, 2012
The Stats Go Marching In
Should Pitchers Change Their Between-Innings Routine?
When the third out is recorded, the pitcher goes back to the bench, puts on a jacket (or wraps a towel around his throwing arm), and sits on the bench for the other half of the inning. When his teammates are retired, he slowly trots back to the mound and delivers a handful of warm-up pitches, and he’s ready to go.
In one of my previous columns, I noticed that pitchers throw their fastballs slowest when there is nobody out and the bases are empty—in most of the cases, that’s at the beginning of the inning. One of the questions that came to my mind was whether they are a bit rusty after spending some time doing nothing on the bench.
In this article, I will look at whether the pitchers’ performance is worse when facing the first batter after resting on the bench, and whether such a difference in performance would indicate that a change in behavior is required.
Let’s start with some numbers.
In the last couple of seasons, the average (linear weights) runs a pitcher allowed when facing the first batter of the inning has been 0.122. When facing hitters number two and three, it’s been 0.116.
The above numbers are relative to starters only, and first innings are removed for a couple of reasons: