All you need to know: Hank Conger: good. Jeff Mathis: poor. (graph from Fangraphs)

Friends Don’t Let Catchers Manage Catchers

Hank Conger is a damn fine baseball player. So far in 2011, based on 73 plate appearances, he’s the 10^th-best catcher in the big leagues by wOBA (that’s weighted on-base average, an awesomely handy all-inclusive hitting stat that scales to batting average). Conger is 23 and has played in a total of 33 big league games. I think it’s safe to assume that he’ll move up that list as he adjusts to major league pitching and the rigors of the game at the highest level. (Baseball players typically peak around age 29 or 30, although that number might be a bit lower for catchers, just because of the physical demands of the position.)

His teammate Jeff Mathis is 28, so we should be expecting him to be at or approaching the peak of his career. Mathis has had almost the same amount of plate appearances – 75 – and is dead last among all catchers in major league baseball at a paltry .217 wOBA. Looking at players with a minimum of 70 PA this year, Mathis is the sixth-worst hitter in all of baseball. This doesn’t appear to be an outlier – his BABIP is at .250, which is in line with his career numbers, and the .217 is probably in the neighborhood of his true talent level (he posted a .223 wOBA last year in 218 PA).

Yet, somehow, Mike Scioscia insists on giving him as many starts as Conger, who could be a star for years to come. Why in the wide, wide world of sports would he do that?

My hunch is that former-catcher managers (of which Scioscia is one, and San Franciso’s Bruce Bochy is another) believe catchers have far more effect on the outcome of the game than they actually do. Yes, the way a catcher calls a game, frames the ball, and handles the pitcher all have an effect on the game, but it’s pretty minimal. (Lots of people FAR smarter and more knowledgeable than me have tried to quantify the effect of a given pitcher on how pitchers pitch, and the result is that it probably does (exist, that is) but that it’s pretty negligible.) So they stay with guys who they believe are good defensive catchers far longer than they should.

If Mathis continues his execrable performances at the plate, Scioscia will be forced to give Conger the bulk of the starts. Probably the worst possible outcome for Angels fans would be for Mathis to “get hot” or go on a crazy unsustainable BABIP-fueled streak. That would probably allow Scioscia to continue to platoon Mathis and Conger for the bulk of the season.

Best possible case? Probably for Mathis to go to the DL with a pulled suck muscle and let the kid handle the bulk of the catching from here on out. Conger has already posted .5 WAR in just 20 games (compared to Mathis’ -0.2 WAR), so, given enough playing time it’s reasonable to believe that Conger could rack up ~2.5 WAR, whereas Mathis’ career high is 0.2 (2007).

In an AL West race that promises to stay tight throughout the season, the difference between Mathis and Conger could make all the difference. 

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