Joe Sheehan wrote an article earlier this month at Baseball Prospectus about how most teams are using their best relievers (closers) very inefficiently. He makes a pretty straightforward argument: "a manager wins baseball games by getting his best players into the highest-leverage situations." Just as you structure your lineup to get runners on base when your best hitter comes up to bat, you should also use your best pitchers in those situations when the game is most likely to be lost.
Let's consider an example: it's the 8th inning of a 4-2 game. Your team is ahead and your starter has pitched well all game, but he just allowed a single and a walk to start the inning, bringing up their best hitter with the tying runs on base. With a pitch count of 102 and the game on the line, it's time to pull him. You have your setup man and your closer in your bullpen. Which pitcher would you choose?
Almost all major league managers these days will use their #2 reliever in this situation, saving their best reliever to start the 9th inning when no one is on base. This defies all logic. The game is on the line, and yet you don't bring in your best pitcher to extinguish this threat? Wouldn't it be better to have your best reliever take care of that problem, and then turn the ball over to a lesser pitcher to start fresh in the 9th? Why save your best pitcher until after the principal threat has passed?
To his credit, Jerry Narron really seems to understand this:
"Some people have the mindset that you bring in your best pitcher in the seventh or eighth inning, because that's when the games are won or lost," Narron said.
"I have all the confidence in the world in bringing Coffey into games with men on base. That's what might keep him in that seventh- and eighth-inning role — his ability to do that. It's not easy coming in with men on base and face the middle of the order."
I have a feeling that there are a number of managers out there who feel the same way. The problem is most likely that the pitcher who finishes the 9th inning gets a save, and that the save statistic equals money and prestige. So long as you have a guy who can fairly reliably pitch a scoreless 9th inning--David Weathers, for instance--it makes a great deal of sense to keep your best pitcher in a set-up type role. Coffey can shut down the other team when they start to rally. If that's happening in the 8th inning, that's when I want to see him.