What is the Side in Baseball?

Unlocking the mystery of the 'side' in baseball: understanding the origin and meaning of the term
Written by Mark Bailey
Last updated on

In baseball, “retiring the side” refers to when the defense gets three offensive players out in a half-inning. When the announcer says “the side is retired,” it means that the half-inning is over and the teams will switch from batting to fielding or vice versa. This can happen through strikeouts, flyouts, groundouts, or any other play that results in outs.

  • In baseball, the term “side” refers to one-half of an inning.
  • The term comes from cricket, where teams are referred to as “a side.”
  • In baseball, the term can mean a team’s turn to bat or their half of an inning.
  • Striking out the side does not have to be done in three consecutive hitters.

Explanation of the term “side” in baseball

The term “side” in baseball refers to one-half of an inning. In baseball, there are no quarters, periods, running clocks, or halftimes. The way to measure the progress of the game is by innings. If someone tells you there are 5 minutes left in an NBA game, the context is clear for the game situation and how much time is left. It is easy to understand.

Baseball measures game progress and time differently.

A professional baseball game consists of nine innings, and each inning is broken down into several parts. Here is where different names can be confusing. Below is a list of phrases and their alternate names and meanings:

Inning: the basic unit of play in baseball. An inning consists of two halves, frames, or sides that are separated by the middle of the inning break. During each half, frame, or side, the batting team gets three outs, making for a total of six outs per full inning.

So, when you hear the term “the side” in baseball, the speaker is referring to one-half of an inning belonging to one team. To hear the term being used in real-time (and to see one of the best pitching performances of all time), watch the video below of this regular season game from 2001 in which Hall of Famer Randy Johnson “strikes out the side” in Pittsburgh and listen to the announcers as they talk about each side he struck out during the game. 

The role of the side in baseball

Sports historians found multiple phrases, terms, and gameplay rules for the game of baseball came from the game of cricket. As an organized game, cricket is over 500+ years older than baseball, yet people can still see the consistencies between the two games.

For example, take the use of the word “side.” In cricket, teams are referred to as “a side,” which is still used today. As the game of baseball developed in America with rules and gameplay, the games began to look different. However, the terms and phrases stuck around. In the early days of baseball, a team was also called a “side,” and when it was that “side’s” turn to bat, the term also meant their “side of the inning,” meaning either the first half or the second half.

Examples of the use of the side in baseball

In today’s games, baseball announcers still use the term “the side” at the end of a team’s half of an inning. But there are more uses than just that. Below are some examples of the use of the phrase “the side” in baseball.

  1. The home team is a dangerous side with great hitting and pitching. 
  2. When we begin the next inning, the Expos side is coming to bat.
  3. With four innings complete, we move to the top side of the 5th inning.
  4. The pitcher strikes out the third hitter this inning, and the inning is over. He struck out the side.
  5. With that ground out, the inning is over, and the pitcher has retired the side in the 8th inning.

In each of these scenarios, you should notice that the term “side” in baseball is a synonym for several terms:

  1. Side = Team
  2. Side = Half Inning
  3. Side = 3 outs one team gets in their half of an inning


Does striking out the side need to be in order?

No, striking out the side does not have to be done in three consecutive hitters. The side is referencing the team up to bat and all three outs that they are allowed. Once three outs are recorded, the side has been retired, and if each out was from a strikeout, then the pitcher has “struck out the side.” It does not matter if the batting team has runners on base, scores a run, or does nothing at all. If all three of their outs during their side of the inning are strikeouts, then the side has been struck out.

There is a special designation for striking out the side in order, and if it’s done in nine pitches, then it is known as an “immaculate inning,” meaning the pitcher only needed to throw nine strikes to record three outs, and no batter hit the ball in play. 

In baseball history, there have been 112 immaculate innings pitched, with the most recent coming from Enyel De Los Santos of the Cleveland Guardians last season. To understand the difficulty of this feat, each MLB team plays 162 9-inning games per year. That means each team plays 1,458 innings. With 30 teams, that means each season contains 43,740 innings. Then consider that baseball has been played for over 100 years.

The bottom line is that are a lot of innings, so for a pitcher to throw an immaculate inning is a big deal. To see two of those 112 innings (they happened in the same game!), watch the video below and join us in trying to understand how the same three hitters of the Texas Rangers fell victim to two immaculate innings in one night.


The next time you are watching or listening to a baseball game, it is pretty certain that you will hear the term “side” being used in various ways. Baseball is a game that changes slowly and holds onto historical terms and jargon. Now that you have the context for some of these terms, you can appreciate the difficulty of striking out the side.

For something really impressive, watch the video below of a 19-year-old Dwight Gooden of the New York Mets (just two years removed from high school) striking out the side during the 1984 MLB All-Star Game in San Francisco.