What Is the Infield Fly Rule in Baseball? A Complete Guide


Left-handed college baseball player in blue and white prepares to catch an infield pop-up.

If you’re watching a baseball game, it can be one of the most frustrating sights to see. Your team has runners on base with less than two outs, about to embark on a big rally. Instead, the batter at the plate sends a sky-high pop-up over the infield, the epitome of an unproductive out.

Usually, the ball is caught without incident, but occasionally it will fall. Chaos! Well, no it isn’t. It’s just an out. The infield fly rule is in effect.

So what is the infield fly rule in baseball?

The infield fly rule declares the batter out whenever he hits an infield pop-up with less than two outs and with runners on first and second or the bases loaded. The infield fly rule is called whether the ball is caught or not. The rule is in place to prevent fielders from deceiving baserunners.

To the untrained eye, it seems like a silly rule. Yes, the ball is caught probably 99% of the time, but why does an automatic out for a ball in play exist? We’ll get into that a little bit later, but first, we’ll go in-depth about what the rule is:

What Is the Infield Fly Rule in Baseball?

The infield fly rule exists in most situations with multiple runners on base and less than two outs. It is unique in that it is the only rule in Major League Baseball where a ball is batted into play but does not necessarily have to be caught by a fielder to result in an out.

The infield fly rule is in effect with the bases loaded, or runners on first and second, with either zero or one out. The rule states that a batter will automatically be called out on a pop fly that can be caught in fair territory by an infielder with ordinary effort.

There are a few important things to distinguish with the rule. First, the rule only applies to fair balls.

In other words, even if the criteria for outs and baserunners are met, an infield fly cannot be called on a foul pop-up, in case the ball is dropped, which would result in just an ordinary foul ball.

Additionally, the phrase “can be caught by an infielder with ordinary effort” is an important one. This can cause confusion in some cases. With this phrase, an infield fly does not mean that the ball must be caught on the infield dirt or grass.

Also, just because an infield fly can be caught by an infielder, doesn’t mean it has to be.

In other words, if a high pop fly is hit into the shallow outfield and an infielder goes out to make the catch but is called off by an incoming outfielder who makes the catch (or drops the ball), the infield fly rule can still be enforced, as long as the infielder was deemed to be able to make the catch with ordinary effort (i.e. was in position and waiting for the ball to come down).

Because of this criterion, there is umpire judgment involved in some cases as to whether a situation calls for the infield fly rule or not.

How Does the Infield Fly Rule Work?

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With the infield fly rule requiring umpiring discretion in some cases, coaches and players need to be aware of what to look for in a potential infield fly situation.

When a pop fly is hit in an infield fly situation, at least one umpire (often an umpire on the bases) will point upward with one finger and declare, “infield fly; the batter is out,” while the ball is in mid-air. The call should always be made before the ball lands.

Once the call is made, the decision is final and the batter will not be allowed to reach base even if the ball falls to the ground. The only exception is on a ball that may land in foul territory.

In this case, an umpire may declare, “infield fly, if fair,” indicating that the infield fly will be invoked if the ball lands in fair territory, but will not be called if the ball falls in foul territory.

The timing of the umpire’s call is important because this affects the fate of the runners on base. When the infield fly is called, the batter is automatically declared out, meaning that any runners on base are not required to advance if the ball is not caught.

What is important to note with baserunners, however, is that they are allowed to advance at their own risk. If a baserunner chooses to advance on an infield fly, there is no force play in effect, meaning that the runner must be tagged to record an out.

However, this is rare since most infield fly situations occur close to the base runners, making further advance difficult.

If there is a pop fly (or more likely, a shallow fair fly ball to the outfield) that falls without being called an infield fly, the batter is not automatically out, and all runners must advance at least one base or be at risk of being put out.

Because these calls can take place in a split-second, confusion can occur, though more on that later.

Why Does the Infield Fly Rule Exist?

As stated in the open, the entire premise of the infield fly may seem silly to a newcomer to baseball, but once you see it and understand the idea, it makes sense.

The infield fly rule exists to prevent fielders from deliberately dropping an otherwise routine infield pop-up to turn an easy double or triple-play by exploiting the opportunity for the multiple force plays.

Without the infield fly rule, in a situation where multiple force plays exist, a fielder may let a ball deliberately drop at his feet, then immediately begin a double or triple-play because the baserunners stayed close to their previous bases to avoid being doubled off in the event of the ball being caught, as would be expected.

For example, with the bases loaded and one out, let’s say a batter hits a high pop fly a few feet in front of home plate.

With the infield fly in effect, the batter is out and the three runners would stay put, leaving the bases loaded with two outs regardless of whether a player catches the ball.

However, if the rule did not exist in this scenario. The catcher could let the ball fall, then immediately pick it up, step on home plate for one out, then throw to third for two outs, and possibly even onto second base for a triple-play (assuming there were no outs).  

In this hypothetical scenario, the baserunners are put in a unique situation where they could be forced out on a dropped pop-up if they stayed close to their previous base, or instead doubled off their base on a caught pop-up if they chose to advance towards the next base while the ball was still airborne.

It should be noted that with runners on base, but not in an infield fly situation, fielders will occasionally let a pop-up (or even a line drive) deliberately hit the ground to turn a double play against an unsuspecting baserunner, or just to force out a faster runner that was on first base.

These types of plays are legal, so long as the ball hits the ground first and is not deliberately batted to the ground with the fielder’s glove.

If a fielder does deliberately bat the ball to the ground with his glove, the play would be called similar to the infield fly, with the batter called out and runners returned to their original bases.

When Was the Infield Fly Rule Implemented?

Black and white photo of a baseball lying in the dirt.

Many of the modern rules of baseball came into play during the 1890s and 1900s and the infield fly is no different, thanks in part to situations like what our hypothetical scenario from the last section listed out.

Indeed, the current version of the rule has largely remained unchanged for over a century.

The infield fly rule was instituted before the 1895 season in response to incidents involving fielders deliberately dropping pop-ups to turn double-plays, in addition to resolving additional confusing language that existed in earlier rules.

Since its inception, the infield fly rule has applied only in bases-loaded situations or with runners on first and second. However, the rule only was implemented with one out in an inning in its initial form.

By 1901, though, the rule was amended to implement the infield fly with no outs as well.

In the rule’s earliest forms, the infield fly applied to line drives and popped-up bunts. Line drives were excluded from the rule in 1904 and bunts were excluded as well in 1920.

The most recent change occurred in 1931, which removed confusing verbiage for the seldom-used term “momentarily held.”

That term under the rule essentially prevented fielders from beginning to catch the ball, only to deliberately drop it.

However, the rule did not protect baserunners when fielders let the ball fall untouched and it proved to be difficult to enforce, so the term was erased from the rule book and replaced with the current wording that protected the runners even when the ball isn’t caught.

What Happened in the 2012 NL Wild Card Game?

Unquestionably the most famous (or infamous) application of the infield fly rule occurred in a crucial situation in the very first National League Wild Card Game, which pitted the St. Louis Cardinals against the Atlanta Braves on Oct. 5, 2012.

With Atlanta trailing 6-3 in the eighth inning, they had runners on first and second with one out. Andrelton Simmons hit a high pop fly into shallow left field that shortstop Pete Kozma called for, then backed away from, resulting in the ball falling, but an infield fly was called and Simmons was out.

Instead of having the bases loaded with one out, as it initially appeared, Atlanta instead had two outs and runners on second and third. They would not score in the inning, or the rest of the game and their season ended that night.

Along with the fact that the play occurred in a winner-take-all game, the call was so controversial because Kozma appeared to have the ball measured up, only to vacate the area when it appeared that left fielder Matt Holliday would instead catch the ball, only for Holliday to let it fall.

By the letter of the rule, Kozma had stopped backing up and raised his arms outward to call off Holliday, before suddenly running forward and giving way to Holliday.

Umpire Sam Holbrook, who was very close to the play (working the left-field line), made the call, though there was some confusion given the fact that the call was made later than most infield fly calls, with the ball rather close to the ground.

The immediate aftermath of the call was striking, with Braves fans voicing their displeasure by pelting the field with debris, forcing a 19-minute delay before play was resumed.

Atlanta ultimately played the rest of the game under protest, which was subsequently denied by Major League Baseball. However, media outlets such as Bleacher Report and USA Today agreed that the call was correct.

This call proved to be an unusual outlier, as most infield fly scenarios are rather cut and dry.

However, because the infield fly rule does not give any firm boundaries in terms of how far into the outfield the call can be made, there can be infield fly calls like this that are more 50/50.

With this knowledge, you now understand what exactly can happen when the batter sends a ball high into the air that is going, going…nowhere.

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Steven G.

My name is Steven and I love everything sports! I created this website to share my passion with all of you. Enjoy!

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