This is a small thing, possibly a very small thing given the dubious utility a LOOGY provides, but one of the real pleasures of the 2012 Yankees season has been seeing lefty Clay Rapada establish himself in the bullpen. With 35 appearances, Rapada has already blown away his season high (32, set last year with the Orioles), raising the intriguing possibility that he might make it through an entire season without being demoted.
As a sidearming spot reliever, Rapada's blessing has also been his curse. He's extremely hard on left-handed hitters, holding them to .150/.247/.220 over the course of his major league career, but pitchers with his approach almost always have massive platoon splits-opposite-side hitters tend to get a nice long look at their pitches. Coming into this season, Rapada's splits have been extreme even by that standard, with all right-handed hitters averaging .359/.474/.692 against him coming into this season. Just to get a sense of how bad that is, Babe Ruth was a career .342/.474/.690 hitter.
This season, Rapada has held right-handers to a homerless .238/.407/.333, which is not good, but it's not Babe Ruth, either. Given those rates have been compiled in just 27 plate appearances, one worries that they're going to revert, but for now that success is part of the reason he's been able to stay in the major leagues.
The versus-righties numbers are important because Rapada has been wild, walking five batters per nine. This is a problem with lefty spot relievers in general: they are on the roster to pitch to very specific hitters, but if they're too prone to walks, you can't predict who they will actually pitch to. If, say, you bring in your lefty to pitch to Adam Dunn and he winds up passing him to bring up Paul Konerko, you either have to make a pitching change or take your chances. Both moves have real consequences. It is for this reason that managers and general managers would often be better off stocking their rosters with the right-hander who is the 11th-best pitcher in their organization than the left-hander who is 20th-best; the strategic matchups they are contemplating often fail to materialize.
Even as well as Rapada has done so far, his utility is limited for those reasons-even with his new "improved" numbers against righties, he should always force that pitching change if a right-handed batter comes to the plate. The Yankees might well do better to put another pitcher in his roster spot, regardless of which arm that hurler throws with. (Alternatively, they could go down to 11 pitchers and give Joe Girardi one more player to work with, but that's a radical notion in today's game.) Still, it's a pleasure to see a journeyman make good at 31... last night's error notwithstanding.