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All sports have terms and acronyms unique to their game, which can be fun, and even helpful for new fans.
The term “SU” refers to “Set-Up,” one of a list of roles that could be assigned to a pitcher. The “set-up pitcher” or ‘set-up man is a hurler that a manager assigns to a role to pitch just before the final pitcher, the “closer.” Typically this is in the 8th inning of games, but not always.
Set-up pitchers is a relatively new term, compared with the nearly 150 years of Major League Baseball.
Until the 1970s, relievers were all the pitchers not good enough to be starting pitchers, that is, the hurlers chosen to begin games. For a very long time, starters tried to pitch entire games (and often did), and relievers were only brought in if the starter got hit hard by several batters, let in a lot of runs, or got hurt, tired, or sick.
And for the longest time, the manager chose which reliever to do so during the game. He often made the selection based on how long he expected the reliever to pitch, as in how many innings. It was more a decision of stamina and, sometimes, the opposing team. Not a lot of deep thought was given to roles for all the relievers.
Then came the “save” statistic and the “fireman,” and later, Tony LaRussa and the 1-inning closer. From then-on, managers really started strategizing about the use of their bullpen, including the assigning of roles.
The SU in a bullpen is not a “position”; it is a role. As such, managers can be either firm on their 8th-inning man, split the 8th between lefties and righties as needed, or not use one at all, relying instead on choosing the next pitcher per the situation.
How is the SU Acronym Used in Baseball?
Many acronyms represent defensive players in baseball, like CF for the centerfielder, or 2B for the second baseman (or to denote a double in the scorebook).
However, the acronym you won’t often see on a roster is SU. That’s because, again, it’s not a position. Pitchers are listed on rosters (and lineup cards pre-game) as simply pitcher. The scorekeeper and home plate umpire don’t care what kind of pitcher.
The acronym is more commonly used in video games, like MLB The Show and Out of the Park Baseball.
A manager might write out SU on his own notes or scorebooks, or in documents shared internally with players. The term “setup man” may be mentioned consistently, but in reality, whoever the SU or setup pitcher is for a team is in the manager’s head.
What is the Purpose of an “SU Pitcher”?

The SU pitcher is often thought of as the second-best relief pitcher on a team. However, there are certain responsibilities assigned to set-up pitchers all in the name of preserving the lead in a game.
Simply put, the setup man might be thought of as a Closer who throws before the final Closer.
Many Closers get their promotions in the bullpen through the set-up role. A famous case is Mariano Rivera, who pitched the 8th inning for a couple of years before being called upon in the 9th.
Here are some of the responsibilities and roles carried out by Set-Up Pitchers.
Set-up Pitchers Maintain the Lead for the Closer
Set-up Pitchers often don’t get the recognition and credit they deserve. Their role is to not let the opposing team score, so the manager can then hand over the rest of the game to the Closing pitcher.
They usually enter the game during a Save Opportunity or SVO but are eventually eliminated from the game before completing it and getting their share of credit for a Save.
The importance of certain relief pitchers was difficult to ascertain for quite some time, except for the Save stat. Today, baseball leagues also track what are called “Holds” ~ when a relief pitcher comes in and does his job. That is, to hold the other team at the same number of runs as when he entered the game.
Best Set-Up Pitchers Often Promoted to Closers
Many Closers gain that status by working their way up the bullpen’s ladder, to ultimately be trusted with the quite important set-up role.
Closers and set-up pitchers share some common characteristics. They both specialize in pitching for a short time, usually one inning. And they both have nasty pitches that result in a lot of strikeouts.
In short, baseball has evolved to where managers acknowledge the vital importance of the last 3 innings of games, and manages his bullpen accordingly. Think of relief pitchers as weapons; and the manager has to decide when to unleash one.
Set-Up Pitchers: Measured by the Hold (HLD)
Eventually, a statistic was invented to measure how the set-up pitchers performed. The Hold (or HLD in box scores) was introduced in the 1980s, and gained value in subsequent years.
A Pitcher needs to earn a Hold by entering the game during a Save Opportunity, and maintain the lead in any of the following situations:
- Enter the game with the tying run on-deck, or
- Enter with the tying run at the plate, or
- Enter with the tying run on the bases.
Why is the Hold Statistic Important?
In baseball, the starters and closers are the two most essential pitchers that receive the most attention from fans and the media. However, amongst all this, the performance and recognition of middle relievers are often overlooked.
A Hold statistic is crucial because it helps highlight how middle relievers contribute to helping the team win.
Through Hold, a pitcher proves his effectiveness in maintaining the team’s late-inning lead. A Hold is only available when the team is up by three or fewer runs. These innings are high-stakes.
Pitchers who accumulate a lot of holds are usually more trusted by coaches. The higher number of Holds proves that the pitcher has proven effective and can perform effectively in high-pressure situations.
Frequently Asked Questions
1. Can more than one pitcher earn a Hold?
More than one pitcher can earn a Hold in the same game. If the first pitcher successfully holds the game, then the pitcher that follows them can also earn a Hold if they record one out and leave the game with a lead.
Eligibility to earn a Hold for any pitcher:
- Enter the game with a 3-run or fewer lead
- Record one out
- Maintain the lead
The Holds can be earned by all pitchers regardless of how many throw.
2. Can Pitchers become Closers?
Yes, absolutely. Pitchers can be upgraded to Closers ~ in fact, it happens all the time. The Closer role is volatile, and as such those who fail repeatedly to end games with a win are replaced by another pitcher who the coaches think will do better. Also, since Closers only have to throw a single inning (mostly), they often do it with full energy and exertion, which results in injuries to muscles and tendons.
3. Who owns the most career Holds?
The record for the most career Holds is held by Tony Watson, a left-handed pitcher. He began his career in 2011 and has collected 246 Holds in his career.
He still plays Major League Baseball and could add to his lead. Before Watson, the record was held by Arthur Rhodes, with 231 holds.
See Also:
Why do Pitchers Wear Jackets on Base?
What is the Average Velocity of a Division 1 Pitcher?
MLB Pitcher: 15 Things You Should Know
Top 17 Slowest MLB Pitchers in History