Pitch count

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 because of his 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. 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. 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 pitches 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 number of 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.

Little League has imposed a strict pitch count limit on pitchers. A pitcher must be removed immediately upon the current at-bat or the current half-inning ends, whichever comes first, upon reaching the pitch count per day.

Once a pitcher throws 21 pitches (under 14) or 31 pitches (15–18) in a game, the pitcher must rest and not participate in pitching. Furthermore, pitchers may not be catchers if more than 40 pitches were thrown by the player.

"Of all the poisonous trends to seep into the game over the past three decades few have done more damage to pitchers than the obsession over pitch counts."

Before pitch counts became prominent in the 1980s, a pitcher primarily "pitched until he could no longer get anyone out or the game was over." As pitch counts have become more prominent, pitchers are often removed from games independent of whether or not they are tired or still pitching effectively. The use of pitch counts has been influenced by agents wanting to protect their clients, and organizations wanting to protect investments in their pitchers. This change has shifted the expectations of starting pitchers from pitching complete games to quality starts of six innings instead.

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