Once more, with gusto: Relievers are fungible!

Yes, there are some superstar relief pitchers. And yes, you can assume that some of them will still be superstars in a year or two. It’s just very difficult to know which ones. Let alone which of today’s unknown bullpenners will be tomorrow’s big-time closers. 

Case in point?

Now, Jason Grilli does have a history. Just two years ago, he racked up 33 saves with the Pirates and pitched in the All-Star Game. But just one year ago, BASEBALL seemed to think Grilli’d been a one-season wonder, as the Pirates traded him to the Angels for Ernesto Frieri in a classic my-problem-for-your-problem deal. After last season, Grilli signed a free-agent deal with the Braves: two years, $8 million. Granted, that’s real money for me and you. For a major leaguer, though, that’s just barely getting by.

And as Jon points out, Grilli wasn’t supposed to be the closer this season. The closer was supposed to be Craig Kimbrel, whom the Braves traded the day before Opening Day.

Then there’s Familia, who’s the closer only because the incumbent got busted for using sports drugs.

Including Grilli and Familia, a dozen major leaguers have earned at least four saves this season. Of those dozen, only five might have been considered star closers just a couple of weeks ago: Kimbrel, Huston Street, Greg Holland, Zach Britton, and Trevor Rosenthal. If you want to get liberal, you might also include Santiago Casilla and Drew Storen in the group, on the strength of their 1.70 and 1.12 ERAs last season.

But that still leaves five pitchers who probably wouldn’t have been drafted in most fantasy leagues just a few weeks ago: Grilli, Familia, Andrew Miller, Joakim Soria, and Brian Boxberger. Not the casual leagues, anyway.

That’s some tremendous turnover!

More to the point, it’s tremendous turnover in the space of less than a year.

In 2011 – and I’ll spare you the math: that’s just four seasons ago – eight pitchers saved at least 40 games: Jose Valverde, John Axford, Craig Kimbrel, J.J. Putz, Mariano Rivera, Heath Bell, Drew Storen, and Joel Hanrahan. Five more guys earned at least 35 saves, and you’re going to just love this list: Francisco Cordero, Brandon League, Juan Carlos Oviedo, Brian Wilson, Chris Perez.

Granted, Oviedo’s sort of cheating; pitching as Leo Nuñez through 2011, he actually racked up 92 saves from 2009 through ’11. He does underscore the general thesis, though, because since 2011 Oviedo’s earned exactly one save.

My point isn’t that relief pitchers are relatively fungible (which is obvious) or that relief pitchers are fundamentally less consistent than starting pitchers. Which seems obvious, but might not actually be true. While relievers’ ERAs and other numbers do fluctuate quite a lot, much of that can be explained by the vagaries of relatively small sample sizes. The fewer innings you pitch, the higher the likelihood that your “true” abilities won’t be reflected in your ERA, or even your other, “peripheral” statistics.

I won’t suggest that relief pitching isn’t important. This season, Kansas City’s relievers have given up only three runs in 42 innings. That’s important. I won’t suggest that individual relief pitchers aren’t important. The Royals aren’t in the World Series last October without Wade Davis and Greg Holland.

What I will argue is that it’s exceptionally difficult to plan these things … but that a smart organization doesn’t need to spend many many millions in the pursuit of an effective relief corps. Four years ago, exactly zero people were seriously thinking about Greg Holland as a relief star. Or Wade Davis. Or Kelvin Herrera.

Last winter, the Dodgers’ new management radically remade the bullpen, which is now younger, cheaper … and, as Dave Cameron points out, a lot better.

Ned Colletti built that old bullpen, and I suppose there are still some Ned Collettis out there, overpaying for dudes like Brian Wilson. But there are more and more Andrew Friedmans and Farhan Zaidis all the time, who understand just how many young, cheap pitchers can throw 95 miles an hour for 20 pitches at a time. For strikes.

Oh, do you remember Ernesto Frieri? The guy who was traded for Jason Grilli last summer, straight up? He struggled terribly with the Pirates, and actually drew his release after just five weeks. Now he’s pitching for the Rays after signing a one-year deal for $800,000 (which is just barely walking-around money these days). He might make it back. But if he doesn’t, he’ll hardly be missed. There are dozens more just like him, happy to toil for the minimum wage.