The Infield Fly Rule Explained: What It Protects Against and When It Applies
The infield fly rule declares a pop-up an out before it lands so a fielder cannot drop it on purpose and turn a double play. Learn the exact conditions, what runners may do and the cases where it does not apply.
The infield fly rule says that when there are runners on first and second base, or on first, second and third, with fewer than two outs, and the batter hits a fair fly ball that an infielder could catch with ordinary effort, the umpire declares the batter out immediately. It does not matter whether the ball is caught or dropped. The batter is out the moment the umpire makes the call, and the runners are left to decide what to do about a ball that is still in play.
The rule exists to protect the offense from a trick. Without it, a fielder could let an easy pop-up fall untouched, because runners standing near their bases are forced to move once the ball hits the ground. The defense could then collect two outs, or even three, on a play that every fan in the park expected to be a routine single out. The rule removes the reward for that trick by making the batter out whether the ball is caught or not.
This article walks through the exact wording, the conditions that must all be true, how the umpire makes the call, what runners may do afterward, and the situations where the rule does not apply even though a pop-up goes up.
The problem the rule was written to solve
Start with the situation as a fan sees it. Runners are on first and second with one out, and the batter lifts a lazy pop-up behind the pitcher's mound. A runner on second base has a choice. If he runs toward third and the ball is caught, the fielder can throw to second and double him off, because he left the base before the catch. If he stays near second and the ball drops, he is no longer safe from the force play, because the runner from first is now moving up behind him. So the sensible runner does neither. He edges off the bag a step or two, ready to go back or ahead, and waits.
That caution is the defense's opening. The infielder camps under the ball and lets it hit the grass. Now the force is on at every base: the runner from first must go to second, the runner from second must go to third, and the batter must run to first. The infielder picks the ball up, steps on third, then second, and throws to first. With runners on first and second that could be a triple play on a ball that, by any normal standard, should have been a simple out.
The infield fly rule is what stops it. It removes the force on the runners and puts the out on the batter at the moment of the call. A defense with an easy catch now has no reason to drop the ball, and the runners now have no reason to freeze. The rule has been part of professional baseball since the mid-1890s, and its purpose has not changed: a team should not gain an advantage from a fielder deliberately failing to catch a ball he can catch.
The exact wording and what each part means
The Official Baseball Rules define an infield fly as a fair fly ball, not including a line drive or an attempted bunt, that can be caught by an infielder with ordinary effort, when first and second base, or first, second and third base, are occupied before two are out. The pitcher, the catcher and any outfielder who has stationed himself in the infield on the play are treated as infielders for the purposes of the rule. Taking each clause in turn:
- A fair fly ball. The ball must be hit in the air and must be fair, or be a ball that could become fair. A ground ball is never an infield fly, however slowly it rolls.
- Not a line drive or an attempted bunt. A line drive is excluded by the definition, and so is a ball hit on a bunt attempt, even if it pops up. In both cases the umpire does not call infield fly.
- Can be caught by an infielder with ordinary effort. This is the judgment clause, and it is discussed in the next section.
- First and second, or first, second and third. Both first and second base must be occupied. A runner on first alone is not enough, and neither is a runner on second and third with first open.
- Before two are out. The rule applies with no outs or one out. With two outs the rule is not needed, and it is not in effect.
- Pitcher, catcher and outfielders playing in. The label "infielder" is about where the player is on the play, not what position he is listed at.
All of those conditions must be true at the same moment. If any one of them is missing, the play is an ordinary fly ball and the usual rules apply.
What "ordinary effort" really means
The phrase that causes the most arguments is "ordinary effort." The rule does not say the ball must stay on the infield dirt or inside the infield grass. The rulebook's comment on the definition says the umpire is to decide whether an infielder could handle the ball with ordinary effort, and that the call is not limited by some arbitrary boundary such as the edge of the infield. The call can stand even if an outfielder ends up making the catch.
The test is therefore about the ball, not the fielder who happened to go after it. A typical infielder, not a spectacular one, would have to be able to reach it without running unusually far or diving. If a fielder misjudges a pop-up and the ball drops, the call can still be correct, because the question was never whether this particular fielder would catch it. The question is whether an infielder with ordinary effort could have.
The call has to be made while the ball is in the air. The rulebook says the umpire shall declare it immediately when it seems apparent that a batted ball will be an infield fly, so that the runners have the information they need as the ball climbs. An umpire who waits until the ball is falling gives the runners less time to decide.
If the ball is near either foul line, the umpire calls "infield fly, if fair." That tells the runners and fielders that the ball is an infield fly only if it ends up in fair territory. If it lands untouched in foul territory it is simply a foul ball, and if it is caught in foul territory the batter is out on the catch.
How the umpire makes the call and what the runners may do
The call has a standard form. The umpire raises an arm and announces "infield fly" and that the batter is out. Any umpire on the field may make the call. The batter is out immediately and has no reason to keep running.
The ball, however, stays alive. Because the batter is out, no runner is forced to move, but runners may try to advance at their own risk, exactly as on any fly ball. If the ball is caught, a runner who wants to advance must tag up after the catch. If the ball is dropped, he may go without tagging, but the defense can now put him out only by tagging him, since the force is off.
A worked example makes the sequence clear. Runners are on first and second with one out, and the batter pops a fly ball behind second base. The umpire calls infield fly, and the batter is out, which makes two outs. The shortstop lets the ball fall, picks it up and steps on second. The runner from first is not out, because no force exists, and the defense still needs a tag to get the third out. Had the shortstop caught the ball, the result would have been the same two outs, and the runners could only tag up.
There is one case that surprises people: a runner struck by the declared ball. If a runner is hit by a declared infield fly before it touches an infielder, the standard rule on a runner hit by a batted ball applies, and he is out as well as the batter, unless he is standing on his base when it hits him, in which case only the batter is out.
When the rule does not apply
Because the conditions are so specific, most pop-ups in a game are not infield flies. The table below shows the combinations.
| Runners | Outs | Infield fly rule in effect? | Why |
|---|---|---|---|
| None | 0, 1 or 2 | No | No runner is forced, so a drop gains nothing |
| First only | 0 or 1 | No | Only one runner; the intentional drop rule covers it |
| First and third | 0 or 1 | No | Second base is open; the intentional drop rule covers it |
| Second and third | 0 or 1 | No | First base is open; no runner is forced |
| First and second | 0 or 1 | Yes | Both runners would be forced on a drop |
| Bases loaded | 0 or 1 | Yes | Every runner would be forced on a drop |
| Any runners | 2 | No | The inning ends on any out, and runners go on contact |
The rule is also not called on a line drive, on an attempted bunt, or on any ball hit on the ground. A pop-up on a bunt attempt is one of the more common sources of confusion. If a batter squares to bunt and the ball pops up near the plate, the umpire does not declare infield fly, because an attempted bunt is excluded from the definition.
The rulebook handles the other cases a deliberate drop could exploit with a separate rule, covered next.
The intentional drop rule: the rule's neighbor
The infield fly rule has a companion that handles situations it does not reach. Under the intentional drop rule, if an infielder deliberately drops a fair fly ball or line drive with first base occupied alone, with first and second, with first and third, or with the bases loaded, before two are out, the ball is dead, the batter is out and the runners return to the bases they held. It covers the combinations the infield fly rule leaves out, such as a runner on first alone or runners on first and third, and it covers line drives, which the infield fly rule excludes. Where an infield fly has been declared, the infield fly rule governs instead.
Two differences matter. First, the intentional drop rule depends on the umpire's judgment of the fielder's intent, since a fielder who simply muffs a catch is not penalized. The infield fly rule does not require the umpire to judge intent at all. It tests only the ball and the situation, which is why it can be declared while the ball is still in the air. Second, the intentional drop rule makes the ball dead, so the runners return. The infield fly leaves the ball live and lets the runners take their chances.
Together the two rules close the gap that the original trick relied on. In the situations where a drop could trap forced runners, one rule or the other takes away the benefit.
The 2012 wild-card game
The most widely remembered infield fly call came in the first National League wild-card game in October 2012, when the Braves hosted the Cardinals in Atlanta. The Braves were trailing in the eighth inning with runners on first and second and one out when Andrelton Simmons lifted a pop-up into shallow left field. Cardinals shortstop Pete Kozma and left fielder Matt Holliday both converged on it, and neither caught it. Left-field umpire Sam Holbrook signaled infield fly as the ball came down, the batter was out, and the Braves, who had thought the bases were loaded with one out, instead had two outs.
Fans threw debris onto the field and play was held up while it was cleared. The Braves played the rest of the game under protest, but a judgment call cannot be protested successfully, and the Cardinals won 6-3. Much of the criticism focused on the timing, since the call came late in the ball's flight. What the episode showed about the rule itself was how the "ordinary effort" test works. The ball fell on the outfield grass, yet the call was upheld because an infielder could have caught it with ordinary effort.
The episode also shows the value of the rule's instruction to call it promptly. A call made earlier gives the runners more time to react. A call made late looks arbitrary even when it is right.
Why the rule is not a gift to the offense
Fans sometimes describe the infield fly rule as a rule that helps the batting team at the expense of the defense. It is better to see it as a rule that removes an exploit. On a normal fly ball a catch is the defense's reward for skill, and the defense still gets it here: the batter is out. What the defense loses is the chance to get more than one out by dropping the ball on purpose.
There is an honest argument that the rule is too blunt. The batter is out even when no fielder touched the ball, and a fielder who really did misjudge it cannot turn the mistake into an advantage. The counter-argument is that the alternative, making the umpire judge each fielder's intent on every pop-up, would be far harder to administer and would invite more disputes. The rule was written to keep the pop-up a simple play.
A softer objection concerns the umpire's judgment. Because "ordinary effort" is not measured, two umpires can disagree about the same ball. The rulebook tries to reduce the disagreement by telling umpires to think of an average infielder and not the specific fielder, but there will always be a few high pop-ups in shallow outfield that spark argument.
Checking the rule at other levels of play
The infield fly rule appears in the rulebooks of professional, college, high school and youth baseball and in softball, though the wording and details can differ from the professional version described here. If you coach or play, check the rulebook your league follows, and ask the league's umpire before the season if a point is unclear.
Scorekeepers treat the play simply. The batter is put out and no hit is recorded, and in the usual case he is charged with an at-bat. The box score shows the out as it would a normal pop-up. To see how those notations read, see How to Read a Baseball Box Score. To practice scoring one, the scoresheet tool lets you keep a game on the page.
Common questions
Can the infield fly rule be called with runners on first and third? No. Both first and second base must be occupied. With runners on first and third, a fielder who deliberately drops a fly ball is handled by the intentional drop rule instead.
Is the batter out if the ball is dropped? Yes. Once the umpire declares infield fly, the batter is out whether the ball is caught, dropped or left to bounce. That is the whole point of the rule.
Can the runners advance? Yes, at their own risk. The ball is live. They may tag up and run after a catch, or run on a dropped ball, but the defense can tag them out because the force is off.
Does a bunt count? No. An attempted bunt is excluded even if it pops up high. A line drive is also excluded. The rule covers fair fly balls only.
Does the ball have to stay in the infield? No. The test is whether an infielder could catch it with ordinary effort. A ball that falls on the outfield grass can still be an infield fly.
Where to go next
Rules that protect runners and batters from tricks sit side by side in the rulebook. Read The Dropped Third Strike Rule: When a Strikeout Is Not an Out for another situation where a batter can reach base on a play that looks like an out, and The Balk Rule Explained: Every Way a Pitcher Can Balk for a rule that protects runners from the pitcher. For more on rules and umpiring, browse the rules and umpiring topic page.