Three Days Rest

Around this time of year, for obvious reasons, there's a lot of talk about pitchers on three days rest. Tangotiger had a post the other day about how pitchers on short rest in the postseason since 1995 have had a 4.37 ERA. Their teams went 39-54, which is a .419 W%. His B-R data is here.

So I started trying to figure out what the average ERA of those guys had been during the regular season, and how much lower it was than 4.37.

In doing this, I realized that a good number of these guys weren't really pitching on short rest. 27 of them had come into a game in relief, and that's why they were showing up in the data. Only 66 of those 93 guys had actually started in their previous appearance. And isn't that what we're really looking at here?

Not surprisingly, the numbers for the guys legitimately pitching on three days rest are even worse. Their teams went 24-42, which is a .364 W%. Here are their stats in the short rest start, compared to their numbers during the regular season.

So their ERA increases by more than a run. I thought it was interesting that their K rate actually goes up, but they give up 42% more HRs, and their BB/9 also increases.

There should also be some kind of adjustment here for the increased quality of offenses in the postseason, but I'm writing this at 3:35AM so I really can't do that right now. I would guess that adjustment is somewhere in the neighborhood of 1/3 of a run.

Both the Red Sox and Diamondbacks have the option of starting their ace on three days rest in Game 4. For Boston, the choice is between Josh Beckett and Tim Wakefield. This year Beckett's ERA was 3.27, while Wakefield's was 4.76. There are two additional factors here. First, Beckett has pitched very, very well on three days rest before. And Wakefield is hurt, hasn't pitched since September 29, and has a 8.76 ERA in his last five starts. (To be fair, Wakefield threw 22 shutout innings in his three starts before that. But still, can they really count on him?)

Beckett could pitch Game 4 and then come back for a potential Game 7 on full rest. Apparently the Red Sox are going to pitch Wakefield on Tuesday- I think I would go with Beckett. Although, as an Indians fan, I guess I'm fine with this.

Arizona's decision is between Brandon Webb and Michah Owings. Owings had a 4.30 ERA this year, compared to Webb's 3.01. If he pitches Monday, Webb would be available for Game Seven on full rest, if the Diamondbacks stage some sort of miraculous comeback. So it would probably make sense for them to go with their ace on short rest as well.

Photo: NY Times.