Sacrifice hit

In baseball, a sacrifice bunt (also called a sacrifice hit) is a batter's act of deliberately bunting the ball, before there are two outs, in a manner that allows a runner on base to advance to another base (with the batter unsuccessfully reaching first base). The batter is almost always sacrificed (and to a certain degree that is the intent of the batter) but sometimes reaches base due to an error or fielder's choice. Sometimes the batter may safely reach base by simply outrunning the throw to first; this is not scored as a sacrifice bunt but rather a single.

In the Major Leagues, sacrifice bunts reduce the average runs scored but increase the likelihood of scoring once. However, they can increase the average runs scored in an inning if the batter is a weak hitter.

A successful sacrifice bunt does not count as an at bat, does not impact a player's batting average, and counts as a plate appearance. However, unlike a sacrifice fly, a sacrifice bunt does not count against a player in determining on-base percentage. If the official scorer believes that the batter was attempting to bunt for a base hit, and not solely to advance the runners, the batter is charged an at bat and is not credited with a sacrifice bunt.

In leagues without a designated hitter, sacrifice bunts are most commonly attempted by pitchers, who are typically not productive hitters. Managers consider that if a pitcher's at bat will probably result in an out, they might as well go out in a way most likely to advance the runners. Some leadoff hitters also bunt frequently in similar situations and may be credited with a sacrifice, but as they are often highly skilled bunters and faster runners, they are often trying to get on base as well as advance runners.

A sacrifice bunt attempted while a runner is on third is called a squeeze play.

A sacrifice bunt attempted while a runner on third is attempting to steal home is called a suicide squeeze.

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Wikipedia