Infield fly rule

The infield fly rule is a rule of baseball and softball that treats certain fly balls as though caught, before the ball is caught, even if the infielder fails to catch it or drops it on purpose. The umpire's declaration of an infield fly means that the batter is out (and all force plays are removed) regardless of whether the ball is caught. The rule exists solely to prevent the defense from executing a double play or triple play by deliberately failing to catch a ball that an infielder could catch with ordinary effort.