Updating the Pinch Hit Penalty, with a Few Rules of Thumb
Pinch hitting is hard. Baseball is a rhythm game, and pinch hitters are denied any semblance of routine. They’re on the bench, swinging a bat back and forth to get the blood pumping in their arms, and then just like that, they’re in the game. They might have been daydreaming about what they plan on ordering from room service, and here’s Jacob deGrom throwing 92 mph sliders. Good luck!
That’s the classical conception of a pinch hitter, and it explains why Tom Tango, Mitchel Lichtman, and Andrew Dolphin found a significant pinch hitting penalty in The Book. They found a 24-point wOBA penalty for pinch hitters, which is a large cost. That’s roughly equivalent to the platoon advantage a lefty gets when facing a right-handed pitcher.
That’s a pretty striking difference. When your team gets a lefty batter up against a righty pitcher in a big spot, it feels great. Imagine that pitcher being replaced by a left-hander. Feels pretty awful, right? That’s the same swing in effectiveness you get when a batter pinch hits rather than batting regularly.
You don’t always hear about this effect on broadcasts, because there are other decisions that go into pinch hitting. You’re getting a diminished version of whichever hitter you select, but other advantages can still tip the scales in a batter’s favor. Read the rest of this entry »