Why do teams need a “setup man?” What would he do any differently than any other relief pitcher? Isn’t the object for relievers (or any pitcher, for that matter) to get the other team out?
The job of the setup man is to bridge the gap between your starter and your closer. He typically pitches the eighth inning of close games that your team is winning. He is your second-best reliever, usually.
Most teams have six or seven relief pitchers. They usually fill a number of specific roles:
Closer - Slams the door on opponents. Used in the ninth inning of games you lead by three runs or less, or when tied in the ninth or later at home. Sometimes pitches all or part of the eighth inning, too, if there are runners on and the game is on the line. Usually a power pitcher who is very tough to hit.
Setup man - After your closer, he is your toughest pitcher to hit. Usually he’s a former closer or a closer-in-waiting. His job is to do the same thing in the eighth that the closer does in the ninth: Keep opponents off the bases and prevent the other team from scoring.
Right-handed long relief - This guy’s stuff is okay, but unremarkable. Unlike the pitchers above, he can regularly pitch two or more innings at a time, several times a week.
Left-handed long relief - Same as above, but this guy is left-handed. Used primarily against opponents that have a lot of left-handed hitters.
Mop-up - Usually the worst pitcher in your bullpen, or the youngest/newest. Often a failed starter. He is used in blow-out situations, especially when the game gets out of hand early and you need someone to pitch four or five meaningless innings.
LOOGY - Lefty One Out GuY. Also known as a left-handed specialist. He comes in to get one lefty batter out—usually the other team’s scariest hitter, who is striding to the plate with runners on base in a tight game.
Mostly, that’s what’s considered good strategy these days. You have a closer, whose job is to get the last three outs and who usually pitches only the ninth inning. That’s been common for some time.
Lately, teams have been looking for a “second closer” – someone who can get the three outs in the 8th inning and give the ball to the closer. That’s what they mean by a setup man.
All relief pitchers are there to get batters out, but a closer is considered the top reliever who you want pitching when the game is on the line in late innings. A setup man is considered nearly as important these days. You wouldn’t use either if your team was losing in a blowout; that’s for the other relievers. It’s primarily a matter of current strategy.
Go back to the 50s and 60s and you were supposed to have two “closers” – left handed and right handed, and relievers got fewer saves because you keep your starter in much longer, usually allowing him to complete the game. Now, the starter only goes 5-7 innings and is removed for a relieve pitcher in most circumstances on the theory that a fresher pitcher will pitch better.
Go further back, and you won’t see relievers except to mop up for blowouts (and find some starters pitching relief, something that’s extremely rare nowadays except maybe in the 7th game of a World Series).
To answer your question directly, you don’t need a “setup man.” You need a corps of good relief pitchers. The “setup man” role, as opposed to the “ace” role, is usually a distinction made on the basis of prestige and/or seniority, not any abilities unique to those roles.
Relief aces in particular are, under current strategic practice, mostly wasted in meaningless situations. Bringing in your best relief pitcher with a 3-run lead to pitch one inning is a waste of his effort; even the worst pitcher in the majors will hold that lead almost every time. You would be better off bringing in your best reliever in, say, a 7th inning tie with two out and two men on.
If you asked various people in baseball about what is the best way to use a bullpen, you will end up with a Great Debate. This is a heated topic among baseball statheads and even among the baseball establishment.
Like much of baseball’s strategy, it has evolved over time and the way bullpens are now used is considered orthodoxy. One of the interesting things to watch in the World Series will be to see how Marlins manager Jack McKeon uses his bullpen, which is decidedly unorthodox.
If you try a new strategy (or revive an old one) in baseball and it doesn’t work at first, the fans and media really hate it.
Hijack - Redsland: your description of the LOOGY made me think of the Simpsons episode where Monty Burns pulls Darryl Strawberry to put in Homer Simpson in order to “play the percentages” against a left-handed pitcher.
If the question is what’s the difference in the pitcher’s ability, here’s a WAG: A closer is supposed to be very, very difficult to hit. Why isn’t he used longer in the game, then? Because usually that “good stuff” is only good for an inning, or two if his pitch count isn’t high. After that his arm is worn out and his effectiveness would drop off quickly. They don’t have the durability of a starting pitcher who can theoretically continue to throw quality pitches for several innings. The setup or middle reliever is perhaps not quite durable enough to be a starter, and not quite as precise as a closer, but good enough to get the team through a couple of innings.
I like the definition I stumbled across in a whimsical-look-at-baseball book about 40 years ago:
Relief Pitcher: not good enough to start the game, not smart enough to worry.
Few in MLB can pitch more than an inning or so per game and make 70+ appearances a season for as many years as possible, which is, among other and more important things, what closers are expected to do.
If the starter can’t last at least 8 innings but his team is still in the game, one of the setup men are often used to try to bridge the gap between starter and closer.