In baseball statistics, pitch count is the number of pitches thrown by a pitcher in a game.
Pitch counts are especially a concern for young pitchers, pitchers recovering from injury, or pitchers who have a history of injuries. The pitcher wants to keep the pitch count low to maintain their stamina. Often a starting pitcher will be removed from the game after 100 pitches, regardless of the actual number of innings pitched, as it is reckoned to be the maximum optimal pitch count for a starting pitcher.[1] It is unclear if the specialization and reliance on relief pitchers led to pitch counts, or if pitch counts led to greater use of relievers.[2] Pitch counts are sometimes less of a concern for veteran pitchers, who after years of conditioning are often able to pitch deeper into games. A pitcher's size, stature, athleticism, and pitching style (and/or type of pitch thrown) can also play a role in how many pitches a pitcher can throw in a single game while maintaining effectiveness and without risking injury.
Pitch count can also be used to gauge the effectiveness and efficiency of a pitcher. It is better under most circumstances for a pitcher to use the fewest pitches possible to get three outs. Pitching efficiency is typically measured by pitches per inning or pitches per plate appearance.
Opposing teams also pay attention to pitch counts, and may try to foul off as many pitches as possible (or at least any difficult-to-hit pitches) either to tire the pitcher out, or to inflate the pitch count and drive a pitcher from the game early in favor of a possibly less effective relief pitcher.