The Infield Fly Rule, Explained
Quick answer
The infield fly rule is called when there are runners on first and second (or bases loaded) with fewer than two outs and the batter hits a fair fly ball an infielder can catch with ordinary effort. The batter is automatically out, whether or not the ball is caught, so the defense cannot drop it on purpose to turn a double play.
What the infield fly rule is
The infield fly rule is one of baseball's most misunderstood rules, but the idea behind it is simple: it stops the defense from cheating its way into an easy double play.
When the umpire calls "infield fly," the batter is automatically out — whether or not anyone catches the ball. Because the batter is out, the runners are no longer forced to advance, which removes the reward a fielder would otherwise get for intentionally dropping an easy pop-up.
When it applies
All four of these must be true:
- Runners on first and second, or bases loaded
- Fewer than two outs
- The batter hits a fair fly ball (not a line drive, not a bunt)
- An infielder can catch it with ordinary effort
If any one of these is missing, it is not an infield fly. The umpire signals it live by raising one arm straight up, usually calling "Infield fly, if fair."
Why the rule exists
Imagine runners on first and second with one out and an easy pop-up to the shortstop. Without the rule, the shortstop could let the ball drop, then start a quick double play at third and second because the runners — forced to advance — would be caught between bases. The infield fly rule makes the batter out immediately so the defense gains nothing by dropping it.
What the runners can do
Because the batter is out, the force is removed and the runners are not required to run. They may:
- Stay on their base (most common), or
- Advance at their own risk
If the ball is actually caught, runners must tag up just like any other caught fly ball before advancing. If it drops, the ball is still live and runners may advance without tagging — but they are never forced to.
Positions Diagram
See where the infielders line up and which fielders are covered by the rule.
Check a real situation
Set the bases, outs and batted-ball type below to see whether the rule applies.
Infield fly checker
Set the situation and see whether the infield fly rule applies.
Infield fly: batter is out
Runners on first and second (or loaded), fewer than two outs, and a catchable fair fly — the batter is automatically out. Runners advance at their own risk.
Frequently asked questions
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The Baseball Tools Team
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