<P> The infield fly rule is a rule of baseball that treats certain fly balls as though caught, before the ball is caught and 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 to prevent the defense from achieving a double play or triple play by failing to catch a ball that an infielder could catch with ordinary effort . The rule is limited to apply only in situations where this result is possible . </P> <P> A ball batted into the air subjects baserunners to a dilemma . If the ball is caught, they must return to their original base; if not caught, the batter becomes a runner and certain runners are forced to advance to the next base . Baserunners study the fielder and advance only far enough from the base to ensure that they can return safely . If a presumed catch becomes a non-catch, forced runners must run forward instead of back . This creates an advantage for the defense in intentionally failing to execute an easy catch, which the infield fly rule exists to remove . </P>

When do you call the infield fly rule
find me the text answering this question