How Many Innings Is Too Many for a Catcher?

Part of a manager’s job is to determine when his players need a breather. For some players, that might be only once a season. For instance, last year in the AL Robinson Cano, Brandon Inge, and Nick Markakis missed just one game each, while Prince Fielder led the NL by playing in all 162 games. When it comes to catchers, though, the question becomes a bit more difficult. Squatting causes plenty of wear and tear, so if a manager wants to get optimal production from the catching spot he has to recognize when his backstop needs a day off.

After starting Yadier Molina in 11 of the team’s first 12 games, including the entirety of a 20-inning affair, I criticized Cardinals manager Tony LaRussa for working his catcher too hard. While Yadier presented a far, far better option than inexperienced backup Bryan Anderson, he also has his limitations. Playing him too much earlier in the season could mean more fatigue down the road. For a team with a catcher as good as Yadier, that can become a rather large issue later in the season.

While Yadier didn’t see immediate ill effects — he hit .375/.438/.464 in the 64 PA following the 20-inning game — he has fallen off a bit lately. Since a 4 for 5 game against Pittsburgh on May 7 Molina has just seven hits in 50 PA, just one for extra bases. We cannot definitively point to Molina’s excessive playing time as a reason for this slump — slumps happen, after all, even to the best hitters in the league — but the correlation is somewhat troubling. Yadier, after all, has caught a large portion of his team’s innings.

Molina is not alone in catching a large percentage of his team’s innings. Here’s a quick breakdown.

Jason Kendall presents the most interesting case here. He has caught by far the most innings of any catcher in the majors, yet ranks among the worst hitters. His .347 OBP is the only saving grace in his line, which amounts to a .309 wOBA, which ranks 19th out of the 24 MLB catchers with at least 100 PA. Is Brayan Pena really that bad? Another good question: will this change with Ned Yost in charge?

Matt Wieters actually ranks worst in this group in terms of wOBA. This is more understandable, because he’s still a young player trying to find his way in the majors. At 83 percent of his team’s innings he’s catching more than most other catchers, which is a concern, but clearly not as big a concern as someone like Kendall, an older player catching nearly every inning his pitchers throw.

All four catchers on the list rank in the bottom half of catchers. Russell Martin started off hot but has cooled off considerably, especially in terms of power. He currently ranks 16th out of 24 qualifying catchers. Molina has caught a slightly lesser portion of his team’s innings, most likely because of Jason LaRue’s return. Still, maybe the extra work early in the season has taken a toll. He currently ranks 18th among peers in wOBA.

Drawing conclusions from this small a sample does no good. We can see that each of these catchers has caught a disproportionate number of his team’s innings, which intuitively sounds like a bad thing for the long haul. Reading too much into their production, however, will not yield any valuable insights. Every player slumps, and we can’t simply pin the poor play of Kendall, Martin, Molina, and Wieters on their playing time. Too may other factors are at work.

What we can do, and what I will do, is revisit this topic and these players throughout the season. I don’t think we’ll find any definitive connections, but perhaps we can gain an insight or two by seeing whether these catchers continue squatting for this many of their teams’ innings.