Yesterday, I casually suggested that the Cardinals adopt a four man rotation for the 2007 season. It would make acquiring a fifth starter unnecessary, and the roster spot that the fifth starter would take up could just be filled by one of the 20,000 relievers currently under contract. The reaction to the idea seemed to be skeptical, to say the least. I, however, would really like to see the question seriously answered. The benefits of this plan would be as follows:
- It gives more innings to Carpenter, Reyes and Wainwright, who are more likely to be good than the Bruce Chen-level player that the Cardinals are likely to sign out of the free agent pool if a stud starter doesn't become availible. Having our best starters throw more innings has an obvious benefit that I won't detail here
- It keeps Braden Looper in the bullpen
- As has been stated previously by both lboros and me (most notably in the context of the 2005 offseason, and the Suppan&Marquis for Vasquez&Quentin trade), for a team trying to win the world series, there is no bigger waste than money spent on a fifth starter--the guy won't pitch in the postseason, will command more salary than many of the guys who will be on the playoff roster. Doesn't it make more sense to spend tha tmarginal cash on a guy who will actually advance your team in the playoffs?
- As has been shown by this series of Baseball Prospectus articles, the four-man rotation doesn't really induce injuries, or, at least, the five-man rotation doesn't prevent injuries. Why are we having a five man rotation if we aren't trying to prevent injuries? After all, pitchers pitched in a four man rotation for the first hundred and ten years that major league baseball existed. Aside from possibbly the change of mound height, what has changed so drastically that pitchers can no longer throw on four days rest? After all, pitchers throw on the side anyway. Here, we'd be eliminating the side session, replacing it with another day of total rest and another start.
I'm not advocating that starter usage progress in the same way that it has in the past--I would limit all of our starters to a very, very strict pitch cap of one hundred pitches, perhaps less for Reyes and Wainwright. Unless the guy is in the ninth inning, and going for a complete game or a no-hitter or something, if he hits a hundred pitches, he is finished. No questions asked. Not throwing with the broken mechanics of a tired pitcher would remove almost all of the 'extra' strain induced by throwing in a four man rotation, right off of the bat.
Really, the only argument that I can see actually working against the four man is, as documented in an old comment here that I can no longer find, Carpenter seemed to have progressively better splits as he had more and more rest last year--turning from a shaky (by his standards only) starter on three days rest to 1968 Bob Gibson on five days rest. If that trend is not just a small sample size fluke, this whole idea might be somewhat counterproductive--you'd be increasing the number of innings thrown by your starters, but the one whose innings would be the most high-impact, for whom you are doing this in the first place, will pitch less effectively after the retooling. In this case, it would not make a ton of sense to give these innings to him.
Anyway, I'm not a baseball trainer, and I can't identify the true trend here, and really say definitively whether or not this would be a good idea. I can, however, say that in pure Moneyball terms, it makes a lot more sense to give this idea a try if it doesn't cause Carpenter's performance to decline. If nothing else, it would sure make a ton of sense skipping the fifth guy's start when an off day would allow for it.
Anyway, that's just my ideal winter idea for the day.
Update [2006-12-20 10:54:52 by Valatan]:: DCGreg finds and cites the stats for Carp on various days of rest.
Update [2006-12-20 15:18:22 by Valatan]:: More on this from Matt at midwest sports fan.