Good luck finding reliable middle men

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The Setup

Once upon a time in baseball, it was easy to find a great pitcher to pitch the sixth and seventh inning. He was known as …

Tonight's starting pitcher.

But nowadays? Uh, it's not quite so easy. Is it?

Here in modern, 21st-century baseball, those innings are being pitched by the scariest, least reliable, least predictable members of any team -- the middle relievers. So in theory, those middle relievers can make a team's whole season.

Or they can get everyone fired except the grounds crew.

So if you're drawing up a formula for how to win, you obviously need to accumulate as many effective middle-relief kind of guys as possible, right? Right. Every GM knows that. But here's what they don't know:

How the heck they're supposed to do that.

Just this week, I asked a very sharp, very experienced general manager if, after exhaustive study on this exact subject, he now knew how to evaluate middle relievers.

"No," he replied succinctly, "because no one does."

And he's right. Middle relief is, by far, the most volatile position in baseball. And we're about to prove it.