1. For a hit.
2. A sacrifice bunt to move a runner over.
Bunting for a hit was usually limited to those batters with great speed who could put a ball in play and beat a throw to first base. That strategy began to lose its appeal as speedsters disappeared when the stolen base was determined to be an ineffective offensive weapon.
Sacrifice bunts disappeared in all but a very limited set of circumstances involving a pitcher at the plate or a scenario late in a game where one run could end the game. That's because advanced analytics were used to determine that it rarely ever made sense in the long run to give up an out just to move a runner up one base.
See #86
“Sacrifice bunts disappeared in all but a very limited set of circumstances involving a pitcher at the plate or a scenario late in a game where one run could end the game.”
They are routine in the National League, even today. It’s rare to see a NL game without a sac bunt.
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