What Is a Fourth Out in Baseball?

Unlocking the Fourth Out: Navigating the Controversial Rule in Baseball
Written by Mark Bailey
Last updated on

In baseball’s rulebook, a fourth out is an anomaly that can occur under specific circumstances, providing a strategic twist. This concept becomes relevant when an appeal play after a third out has the potential to negate a scoring play. Let’s unpack this unusual situation and its implications on the game.

What is a fourth out?

A team must record a fourth out if the hitter who was supposed to be the third out makes it to first base because the third strike is dropped by the catcher, and there are no runners on first.

To clarify, we break it down step-by-step below with the most common example of a four-out inning:

  1. With two outs and/or no one on first base, the hitter has two strikes against them. 
  2. The hitter swings and misses the next pitch for the third strike, but the catcher does not catch the ball.
  3. Because the catcher dropped the ball, according to baseball rules, the ball is live because the batter swung (even though they didn’t make contact).
  4. Because the ball is live, the runner can now attempt to advance to first base. 
  5. The defense must either tag the batter who swung and missed or force them out at first base.
  6. If the defense fails to tag or force out the hitter and they reach first base, they are awarded that base.
  7. The hitter will be credited with a strikeout for the at-bat, and the pitcher records a strikeout too.
  8. Even though the play is scored as a strikeout in the record books, an official out is not credited to the defense because they failed to get the hitter out when the ball was live.
  9. Once the hitter safely reaches first base, they are now a baserunner and can be tagged out or advance bases.

To see this in action, watch the video below from the 2013 AL Championship between the Tigers and Red Sox. This is an example of great situational awareness from Shane Victorino and perseverance from Anibal Sanchez:

History of fourth out

Back in the 1870s, MLB’s official rules stated that batters needed four strikes to be out and needed seven called balls to be awarded first base. But in 1880, that changed. The rule changes that year stipulated that batters no longer received a fourth strike and that the catcher must catch the pitch on the fly to register an out on a third strike.

As you can see, this rule has been around for a long time, but what is surprising is that this kind of play has seen a major comeback in the last 20 years. From 1916-1956, no team recorded a four-out inning. From the ’60s to the ’80s, it was only done 14 times. From 2000 to today, this feat has happened 34 times, just in the National League.

Why is a fourth out important?

A fourth out is important to the batting team because it gives them a chance to get a baserunner and score a run even though the batter had technically struck out. Also, to be clear, all four outs do not have to be strikeouts. It is called a 4-strikeout inning by default because the 3rd out must be a strikeout that was dropped by the catcher.

When a potential fourth-out situation occurs, it requires high situational awareness by the hitter, catcher, first baseman, and even the pitcher. They need to be aware of the count and watch the catcher closely to make sure he catches the pitch without it hitting the ground. If a 3rd strike is dropped on the 3rd out, both the hitter and the defense have only seconds to react to make the play go their way.

Controversies surrounding fourth out

The biggest fourth-out controversy in recent history happened in a regular season between the Nationals and the Pirates last year. In this situation, the outcome was decided based on the MLB “time play” rule. This play was so confusing that it made the headlines in every sports newspaper and publication last summer. 

In fact, the umpire crew chief for the game, Mark Wegner, who has been an MLB umpire for 25 years, went to social media and claimed, “This is the first time I’ve been on the field for something like this.” Watch for yourself. Fast forward to the 3:50 mark of the video, and see and hear the confusion and chaos:


Is it possible to get four outs in an inning?

It is possible to get four strikeouts in an inning, but only three outs are recorded for an inning to be complete. Under the “Fourth Out” rule, the batter who struck out for what would have been the 3rd out of the inning advanced to first base because the catcher could not hold on to the ball on the 3rd strike. This means they technically struck out, and the pitcher receives credit, but the batter can attempt to reach first base on the play. If they do, then the defense must record one more out.

What is the fourth out rule in baseball?

The “fourth out rule” in baseball is a direct result of the dropped third strike rule in MLB. If the team going up to bat gets a runner on base even though they struck out, then that player becomes a live baserunner, and the defense must record one more out.

It makes more sense to read them in order:
1. Dropped Third Strike Rule: The batter becomes a runner when the third strike called by the umpire is not caught, providing that first base is unoccupied or occupied with two outs.
2. Fourth Out Rule: The third out does not cause the ball to become dead. If the hitter becomes a baserunner because of the dropped third strike rule, then the strikeout stands, but the third out is removed, and the next out will be the officially recorded 3rd out.

As it applies to the Pirates-Nationals game we discussed above, there is also the “apparent fourth out” in the MLB rulebook. It states, “Any appeal under this rule must be made before the next pitch or any attempted play. If the violation occurs during a play that ends a half inning, the appeal must be made before the defense leaves the field.”

How do you record four outs in baseball?

When scoring a baseball game, the batter who strikes out yet safely reaches first base because of the dropped third strike rule is credited with a “K,” which signifies that they struck out, but the scorer will also draw a line in the score sheet from home to first base and fill in first base to signify that even though the batter struck out, they made it to first base safely. There is no specific designation in the daily box scores, but four out innings are rare and will be in the news the next day.


It’s not often that teams must get a fourth out, but it happens. Some pitchers have difficult pitches to catch, so catchers are the key personnel to ensure that defenses do not need to chase that fourth out. 

But even if you do need to get one extra person out, having a quality pitcher makes all the difference. Power pitchers like Bob Gibson, Don Drysdale, and Clayton Kershaw always come up in conversation for a good reason—those pitchers throw hard and are strikeout artists. So, even if the catcher drops a third strike and the other team has a baserunner, all is not lost. In fact, you don’t even need a power pitcher like Walter Johnson or Kenley Jansen (both have done it). 

Watch 40-year-old Charlie Hough of the Rangers strike out four Yankees in the first inning of a regular-season game in 1988. If you think his pitches look slow and easy to hit, remember who he struck out: Dave Winfield (Hall of Fame), Jack Clark (4x All-Star), Claudell Washington (2x All-Star), and Mike Pagliarulo (eventual WS Champion). 

  • In baseball, teams must record three outs per inning for the game to progress. The fourth out rule is an exception to the normal three outs, where a batter’s third strike can be caught by the catcher and still allow a baserunner if the first base is unoccupied or if there are two outs.
  • This rule has seen a resurgence in the last 20 years, with 34 instances of it occurring in the National League since 2000.
  • It requires situational awareness from both the offense and defense in order to record an out on a potential fourth-out situation.
  • Controversies surrounding fourth-outs have arisen in recent years, including a notable one between the Nationals and Pirates in 2020 that gained national attention.
  • While rare, four-out innings are possible and require skilled pitchers to make them successful.