"Relievers are relievers for a reason” is a baseball adage. A pitcher with great command of several pitches is a starting pitcher. A reliever has some flaws, but can be strong in one or two pitches.
“A lot of relievers are relievers for a reason anyway” was cited in April 2001 and “Middle relievers are middle relievers for a reason” was cited in July 2001. It’s not known who first said the baseball adage.
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A lot of relievers are relievers for a reason anyway. They may lack stamina or being killed by a lefty or righty may be the other reasons.
8 July 2001, Rockford (IL) Register Star, “Quick Shots: Middle relievers aren’t All-Stars” by Matt Trowbridge, pg. 1B, col. 1:
Middle relievers are middle relievers for a reason—they aren’t good enough to be starters or closers.
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Mateo may have a shot at a major league career, but he’s a reliever for a reason.
29 April 2005, Daily News of Los Angeles (Los Angeles, CA), “Playing a waiting game”:
And, when a (starter) gets his pitch count up, you get to face middle relievers, and those guys are middle relievers for a reason. They make more mistakes and big-league hitters hit mistakes.
1 June 2006, Akron (OH) Beacon Journal, “Dealing with the bullpen is a crapshoot,” pg. C1:
Relievers are relievers for a reason. They usually don’t have as many pitches as a good starter. They also may have more weaknesses.
The Cleveland Indians’ New Ballgame:
How a Small-Market Team Reinvented Itself as a Major League Contender
By Terry Pluto
Cleveland, OH: Gray & Co.
Relievers are relievers for a reason. They usually don’t have as many pitches as a good starter. They also may have more weaknesses. Their edge is slight, and that’s why fatigue or even a minor injury can make a major impact.
River Ave Blues (NY Yankees blog)
February 13, 2010
On the volatility of relief pitchers
By Mike Axisa
“The first thing you’ve got to remember,” said another GM, “is they’re relievers for a reason. The reason they become relievers in the first place is because they have some flaws. They don’t have a third pitch. They can’t repeat their delivery. They’ve got an unorthodox arm angle. So we made them relievers — because if we had a choice, we’d make them starters. Just the fact that we made them relievers means you’re looking at an imperfect crop to begin with.”
Washington (DC) Post
2013 MLB All-Star Game: Stuck with the middle
By Harry Pavlidis, Published: July 13 at 4:05 pm
If he’s not a starter and not your closer, maybe he’s quietly racking up high-leverage appearances. Still, does anyone think he’s among the best pitchers on the team, let alone in the league? As the old saying goes, they’re middle relievers for a reason.