What Is a Sacrifice Fly in Baseball? Rule, Scoring, RBI Explained

A sacrifice fly in baseball is a fly ball hit deep enough to be caught for an out while a runner, almost always from third base, tags up and scores after the catch. It is the rare out a batter wants to make: it counts as a run batted in, but it does not count against his batting average.

Announcers shorten it to “sac fly,” and box scores mark it with the abbreviation SF. Understanding why this one specific type of out gets special treatment explains a lot about how baseball’s scoring rules reward productive outs. Here is the full rule, how it is scored, and how it compares to the sport’s other sacrifice play.

The official rule for a sacrifice fly

Major League Baseball’s Official Rule 9.08(d) defines it precisely. A sacrifice fly is scored when, with fewer than two outs, the batter hits a fly ball in fair or foul territory that is handled by an outfielder (or an infielder running into the outfield) and:

• The ball is caught, and a runner scores after tagging up, or
• The ball is dropped, and a runner scores, if in the official scorer’s judgment that runner would have scored anyway had the fly ball been caught cleanly.

The key phrase is “fewer than two outs.” A fly out with two outs already on the board ends the half-inning the instant it is caught, so no runner can legally score on the play, which means a sacrifice fly is mathematically impossible with two outs.

Why it does not hurt the batter’s average

This is the detail that makes the sacrifice fly unique. Under Rule 9.02(a), a sacrifice fly is one of the handful of outcomes excluded from a player’s official at-bats, alongside walks, hit-by-pitches, and sacrifice bunts.

Since batting average is calculated as hits divided by at-bats, removing the at-bat means a sac fly cannot lower it. At the same time, the run that scores is credited to the batter as an RBI. The result: a hitter can fail to reach base, technically make an out, and still walk away with a better stat line than if the at-bat had never happened.

Outcome	Counts as an at-bat?	Counts as an RBI?	Affects batting average?
Sacrifice fly	No	Yes	No
Sacrifice bunt	No	No	No
Regular fly out	Yes	Only if a run scores	Yes (lowers it)
Base hit	Yes	If a run scores	Yes (raises it)
Walk	No	No (unless bases loaded)	No

How the play typically unfolds

The classic sacrifice fly situation is a runner on third base with fewer than two outs. The batter lifts a fly ball deep enough to the outfield that, once it is caught, the runner can tag up and beat the throw home.

1. The batter hits a fly ball caught by an outfielder (or a shallow infielder running into outfield territory).
2. The runner on third must legally tag up, meaning they touch third base at or after the moment of the catch, before advancing.
3. The runner sprints home and beats (or ties) the throw to the plate.
4. The umpire rules the runner safe, and the official scorer logs a sacrifice fly and an RBI for the batter.

If the runner leaves third base too early and the defense appeals correctly, the runner can be called out for leaving early, but under Rule 9.08(d) the batter still keeps credit for the sacrifice fly as long as a run scored before the appeal out became the third out of the inning.

Sacrifice fly vs. sacrifice bunt

Baseball groups sacrifice flies and sacrifice bunts under the same broad “sacrifice” umbrella because both plays intentionally trade an out for team advancement, and both are excluded from at-bats. The mechanics and the reward are different, though.

• Sacrifice fly: a fly ball caught in the air, scores a runner from third, and is credited as an RBI.
• Sacrifice bunt (sac hit): a bunted ground ball that advances a runner (typically from first to second, or second to third) without necessarily scoring anyone, and it does not earn an RBI.

Both plays are examples of what fans generally call a “productive out,” a batting result that helps the team even though the hitter is retired. For more on how baseball’s less obvious plays and calls are officially defined, see the baseball terminology glossary.

Sacrifice fly leaders and situational value

Sacrifice flies are most common with a runner on third and one out, since a runner on third with zero outs already scores on far more play types, and with two outs the play is impossible by rule. Teams that hit the ball with authority to the outfield, rather than relying on ground balls, tend to rack up more sacrifice flies over a season simply because they generate more deep fly-ball contact with a runner in scoring position.

The situational skill involved, lifting a pitch just deep enough without popping it up or striking out, is closely related to other contact-based run-producing plays like the grand slam at the opposite extreme of power, or the sacrifice bunt at the opposite extreme of small-ball strategy. All three sit on the same spectrum of manufacturing runs in different ways.

Quick recap

A sacrifice fly is a fly out that:

• Occurs with fewer than two outs
• Is caught (or misplayed in a way that still would have allowed the run)
• Allows a runner to tag up and score
• Is not counted as an at-bat
• Is counted as an RBI

It rewards a hitter for productive contact even in defeat, which is why coaches and broadcasters treat it as a genuinely good outcome rather than a failed at-bat. To see how this fits into the sport’s larger rulebook of scoring and situational plays, browse more explainers on the baseball and MLB hub.