Catcher ERA is a horrible stat

According to Ben’s breakdown of Jorge Posada’s CERA, the long-time Yankees backstop has completely forgotten how to handle a pitching staff. After residing in the mid-4s for most of his career, Posada’s CERA has jumped to 6.31 this season. This, of course, means that pitchers don’t like throwing to him and that the Yankees should DH Posada a lot more, because Posada and Cervelli is better than Posada and Matsui.

I’ll knock off the sarcasm there, though I still hold contempt for the idea that Jorge is suddenly a lot worse at handling a pitching staff than he has been in the past. Still think Jorge’s not a good catcher, based on his CERA? Give this BtB article by R.J. Anderson a quick read. He’s not even talking about Posada in this instance. Rather, he’s talking about the league-wide obsession with backup catchers.

Fans seem to fall in with reserve catchers. I don’t know why. I suspect it has to do with the mystique of being a defensive stalwart, one immeasurable by metrics known to man. Perhaps having to sit in the bullpen and warm pitchers up is something worthwhile. These guys are usually horrible hitters, the worst bats on the team that actually get paid to hit. Why? Because if they hit well, they would be playing.

So, you have a player on each team who has writers, fans, and television folk talking up his game calling abilities and whatnot because saying that his entire value comes from squatting for four hours a week isn’t something you take pride in. Eventually it melts in. People start looking for things that feed this confirmation bias of Johnny McBackstop being a human computer. It becomes mainstay knowledge, and now every team in the league needs one of these veteran catchers, good at absolutely nothing outside of history lessons.

He goes on to throw an enormous monkey wrench in the case of CERA, starting with the abstract — there are other factors like ballpark, the pitcher himself, and the defense behind him — and concluding with the concrete — Michael Barrett and Jason Varitek have comparable CERA numbers over their careers.

Jorge might not be the best game-caller. He might not handle a pitching staff the way other catchers do. Those points are up for debate. However, to use CERA in the argument does it no service. The stat simply doesn’t reflect what happens on the field.