If a declared Infield Fly is allowed to fall untouched to the ground, and bounces foul before passing first or third base, it is a foul ball. If a declared Infield Fly falls untouched to the ground outside the baseline, and bounces fair before passing first or third base, it is an Infield Fly.
(Infield Fly) Comment: On the infield fly rule the umpire is to rule whether the ball could ordinarily have been handled by an infielder-not by some arbitrary limitation such as the grass, or the base lines. The umpire must rule also that a ball is an infield fly, even if handled by an outfielder, if, in the umpire’s judgment, the ball could have been as easily handled by an infielder. The infield fly is in no sense to be considered an appeal play. The umpire’s judgment must govern, and the decision should be made immediately.
When an infield fly rule is called, runners may advance at their own risk. If on an infield fly rule, the infielder intentionally drops a fair ball, the ball remains in play despite the provisions of Rule 5.09(a)(12) (Rule 6.05(l)). The infield fly rule takes precedence.
If interference is called during an Infield Fly, the ball remains alive until it is determined whether the ball is fair or foul. If fair, both the runner who interfered with the fielder and the batter are out. If foul, even if caught, the runner is out and the batter returns to bat.