What is the Bullpen in Baseball?

A bullpen in baseball is an area where the relief pitchers warm up, stretch, go over pitching strategy, and more before entering a game. Usually, the bullpen is out behind the outfield walls, but a few Major League Baseball stadiums have theirs in foul territory. In this area, you have the bullpen coach, the relief pitchers, and backup catchers ready to warm up the pitcher to enter the baseball game whenever their team requires them.

So, where did the name come from exactly? Where can fans typically find the bullpen at most MLB venues? What does a relief pitcher do? What does it mean to throw a bullpen session?

Here is the complete guide to what a bullpen is in baseball.

Why is it Called a Bullpen in Baseball?

There are various reasons why people call it a “bullpen” in baseball. To start, the concept of a pen in rodeo has extra bulls waiting in this area until they are ready to enter the action. Since this area resembles that of a rodeo, the name stuck with fans and players.

Another reason why this area is called a bullpen deals with the Bull Durham tobacco ads that were out in the outfield fence at baseball stadiums. Since these ads were so close to where the pitchers were warming up, it became known as the bullpen area.

Where are Bullpens at Most MLB Stadiums?

In most Major League Baseball stadiums, the bullpen is behind the outfield wall. Some stadiums, like the New Yankee Stadium, will have one bullpen out in left-center while the other is in right-center. Other ballparks, like Citizens Bank Field, will stack the bullpens in the same spot. Coors Field, where the Colorado Rockies play, have pine trees in their bullpen area to give it a different look from other places.

However, there are some MLB stadiums where the bullpen is in foul territory and on the baseball field. For example, Tropicana Field, Oakland’s ballpark, Wrigley Field, and Oracle Park have their bullpens on each side of the field directly in front of the first row of seats. Being on either side of the field means that these players must be alert to watch out for foul balls and not interfere with any play with the ball or defender.

What is a Relief Pitcher in Baseball?

A relief pitcher is a player who comes in “for relief” of another pitcher during a game. The reliever can come in after a starting pitcher goes six innings and help bridge the gap to close the final three innings. Relief pitchers can enter the game much sooner if the starting pitcher is struggling at the mound, giving up many runs, or getting injured.

No matter what, relief pitchers need to be able to jump into the action whenever their team requires them, so they must be mentally prepared to go from sitting on the bench to going into the game.

Why Do Relief Pitchers Need to Warm up Before Entering a Game?

During a game, you might see some relief pitchers sitting on the bench or doing light stretching here and there. However, when the phone rings and the bullpen coach tells them which player to get ready, they must warm up. Going from not throwing to throwing the ball in the 90s can cause severe strain to a pitcher’s arm, so players begin to warm up with light tosses in the bullpen and work their way up till they are ready to enter the game.

Also, warming up before entering the game helps shake off the rust from sitting in the bullpen for an hour or two. Especially if the game goes into extra innings, the pitcher could sit on the bench for over three hours. Giving them time to warm up will be crucial since you don’t want a player to enter the game cold and be unprepared to pitch effectively.

If a pitcher does not warm up before entering the game, their pitches might not be as accurate or as sharp as they would like, which could lead to more runs for the opposing team. Also, the chance of an injury dramatically increases when you don’t warm up before entering the game.

Do Teams Call Certain Relief Pitchers for Specific Matchups?

In 2020, Major League Baseball adopted a new standard called the “three batter minimum rule.” That new rule means that bringing in a new pitcher must face at least three batters before they can be removed from the game. However, if the pitcher can get out of the inning even without facing three hitters, like inducing a double play that ends the inning, they can get swapped out at the start of the next inning.

Before that 2020 rule, MLB managers sometimes used one relief pitcher to face a specific hitter in a lineup and then took them out afterward. Most commonly, you would see a lefty specialist enter the game against a left-handed hitter and then leave after facing them, no matter what happened in the at bat.

What is a Bullpen Game?

A bullpen game is when the starting pitcher leaves the game earlier than the team expected. Leaving the game earlier than expected means the manager must go to their bullpen earlier to get the remaining outs. Since most relief pitchers tend only to go about 1-2 innings at most, managers need to use multiple pitchers to get the remaining outs, creating a bullpen game.

Here are three of the most common reasons a bullpen game occurs.

The starting pitcher/s got injured early in the game.
If the pitcher is caught cheating, like having pine tar on their neck, they will receive an ejection.
The starting pitcher/s gave up too many runs early in the game, so the manager took them out.

What Does it Mean to Throw a Bullpen?

Throwing a bullpen session means a pitcher is working on their pitches with the help of the pitching coach in the bullpen area. The idea behind throwing a bullpen session is to work on different pitch types and build up arm strength (especially coming off an injury). Also, starting pitchers will have a 10-15 minute bullpen session between their starts to keep their arms loose, especially if there are off days in the calendar.

How Many Pitchers Can Throw at Once in a Bullpen?

Every bullpen in Minor League Baseball and Major League Baseball allows up to two pitchers to throw simultaneously. It doesn’t matter if both are left-handed pitchers, right-handed pitchers, or one of each. There will be two catchers in the bullpen who can catch any reliever who needs to warm up during a game.

Conclusion: What is a Bullpen in Baseball?

In summary, a bullpen in baseball is an area where the relief pitchers hang out, stretch, and warm up before entering a game. You typically find the bullpens out behind the outfield walls. However, some MLB venues have the bullpen out in foul territory on the field, like Wrigley Field, which means fans can easily see them getting ready before entering the game.