Platoons and Bullpens

Gabe Gross, Ryan Garko, Reed Johnson, and Eric Byrnes have all signed contracts in the past week or so, each settling for under $1 million on a one year contract after shopping their skills around. Each of these guys have some value in part-time platoon roles, specializing in hitting pitchers who throw with a certain hand, but lack a necessary skill to play full time.

Because of the ever increasing size of bullpens, these types of hitting specialists have fallen out of favor. The meager salaries that these guys have had to accept highlights the lack of value that teams are now placing on platoons. With only 13 of 25 roster spots dedicated to position players on most teams, it is becoming far more difficult for teams to accommodate left-right platoons and still have the necessary reserves for their starters in case of injury.

Is that a wise use of roster allocation? I’m honestly not sure. I know there’s been a backlash against the ever increasing bullpen sizes among the sabermetric community, but I haven’t seen much in the way of evidence that specializing your bench is more efficient than specializing your bullpen.

Yes, the 12th pitcher on any given team is usually not very good, often producing at a near replacement level. Even if they pitch decently, the leverage of the innings they are given is usually so low that their overall value is quite low. So a straight comparison between value of platoon guy versus value of the 12th reliever will naturally lead one to conclude that teams would be better off with a larger bench and smaller bullpen.

I think there’s more to it than that, however. While mop-up relievers may not pitch well or handle many important innings, having them around allows managers to use their better relievers in different ways. As we’ve seen in the last decade, the larger bullpens allow managers to mix and match based on handedness in higher leverage situations, using pitchers who are far more effective against same handed hitters.

The goal of platooning a pair of hitters or using bullpen specialists is really the same – get as much value from exploiting left/right splits as possible. So why are managers going more towards pitchers when attempting to exploit those advantages?

I think it’s because they inherently understand the pinch-hitter penalty. As Matthew noted on ESPN a few weeks ago, guys perform at a level nearly 10 percent below their true talent level when being used as a pinch hitter. There is significant evidence that the act of sitting around for a few hours, grabbing a bat, and trying to get a hit is just very hard.

If you try to exploit platoon advantages from the offensive side, you get less than the full value of the hitters you are using when pinch-hitting. Thus, any hitter with a large platoon split can be devalued in high leverage situations in a way that is tough to counter. Even if you pinch hit for the left-handed half of your platoon when the opposing manager brings in a LOOGY, you’re still at a disadvantage, because your right-handed bat now has to overcome the penalty of inactivity.

While it may be annoying to watch the parade of relievers bog down game from the 7th inning on, I think there’s a pretty decent chance that managers are making the more efficient decision. It’s an area that needs more study, certainly, but I think we should acknowledge that there is value to platooning your relievers that is not found in platooning your hitters.

We hoped you liked reading Platoons and Bullpens by Dave Cameron!

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Dave is the Managing Editor of FanGraphs.

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“Yes, the 12th reliever on any given team is usually not very good”

Probably what you’d expect, given that they’re probably only the 5th best relievers on the team’s triple-A affiliate…


Not sure what this means.

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Dave’s line should read “12th pitcher on any given team” rather than 12th reliever.

Having twelve relievers means you’ve already got the standard seven, plus five more … probably from your AAA team. Thus 12th reliever=5th AAA reliever.