When an infield fly rule is called and not caught, what happens to the baserunners?

When the infield fly rule is invoked and the ball is not caught, baserunners have the opportunity to advance at their own risk. This rule is designed to protect the baserunners in situations where a pop-up could lead to an easy double or triple play, as it removes the potential for a fielder to intentionally drop the ball to create such an out. The runners are not required to return to their original bases; instead, they have the choice to advance if they believe it is safe to do so.

This situation underscores the intent of the infield fly rule, which is to eliminate confusion and protect baserunners from unfair plays that could result from the fielder's actions. Therefore, the choice allowing runners to advance serves both to maintain the integrity of the game and to afford the players some strategic options while playing.