I’ve become much more cognizant of platoon splits in lineup construction since we introduced them to the PECOTA cards this year. One example of how they can be a helpful tool in in analyzing the Cubs’ acquisition of Reed Johnson.
Johnson was brought in — ostensibly, at least — to platoon with Felix Pie in center field, while providing some reserve depth at the corner outfield positions. A year ago, I might have blasted this transaction — but the platoon splits make clear that Johnson provides a pretty substantial upgrade over Pie against left-handed pitching:
Player AVG/ OBP/ SLG MLVr per 162 CF Defense
Pie .264/.314/.431 -.008 - 1.3 Good
Johnson .288/.359/.434 +.072 +11.7 Marginal
Murton .310/.380/.488 +.197 +31.9 Piss Poor
You’ll see a couple of stats here that we don’t make nearly enough use of. One of them is MLVr, which is simply the number of runs a player can be expected to produce at the plate relative to a league average player (I’m using the quick-and-dirty version of MLVr, as documented here). I’ve also translated these numbers to a per-162 game basis, which I find a little easier to work with.
Against left-handed pitching, Johnson should be about .08 runs better per game than Pie at the plate, or the equivalent of 13 runs per season in the imaginary, Hank Blalock dystopian world in which every pitcher is left-handed. Does Pie make up those 13 runs on account of his defense and baserunning? It’s actually somewhat close, but probably not; Johnson is a competent center fielder, especially in a small outfield like Wrigley, and apart from that it probably can’t hurt Pie’s confidence to sit him against tough lefties, which means that he’ll see higher batting averages next to his name on the center field scoreboard. So, if these were the only two alternatives in the world, this would qualify as a very small upgrade for the Cubs.
However, there is another option in the form of Matt Murton, who is around .12 runs per game better than Johnson against left-handed pitching — the equivalent of about 20 runs per 162 games — and fully .20 runs better than Pie. Can Murton play center? Probably not in a way that most teams are willing to tolerate. But Murton could play right field — and Kosuke Fukudome could play center, which by most accounts he was able to handle competently in Japan. It’s hard to imagine that a Johnson/Fukudome outfield is fully 20 runs per season better with the glove than Fukudome/Murton; it’s not like Reed Johnson is Gary Maddox out thee. And here, the clubhouse externalities work in the opposite direction, because by acquiring Johnson, you’ve made clear to Murton just how unimportant a part of the club’s future he is.
It’s not a bad acquisition in the abstract so much as an uncreative use of resources, which has become something of a hallmark for the Cubs.