Jonathan Lucroy had Brewer fans excited with his bat early in the season. For much of the first half, he was maintaining a batting average above .280, supplying some decent power, and giving the team a semi-reliable bat out of the catcher position, something that hasn’t been since B.J. Surhoff was around. Over the second half of the season, however, it’s become apparent that Lucroy isn’t really at Surhoff’s level with the bat, as the 25-year-old has managed a mere .242/.295/.343 line since the All-Star break.
Still, Lucroy owns a .263/.311/.384 line on the season, and while that isn’t pretty, it’s good for a 92 wRC+, above the league average for catchers. He enters play Thursday with 1.7 fWAR in 451 plate appearances, slightly above the average player. According to WAR, he isn’t a star, but he is a slightly above average player — exactly what the Brewers needed.
WAR isn’t perfect, however, and one of it’s more major imperfections lies in the realm of catcher defense. Whereas some of the imperfections of the WAR come from questions with existing data (see UZR and other fielding metrics), when it comes to catcher defense, there is largely an absence of data. Currently, fWAR takes catcher defense on stolen bases into account, but that leaves a large part of the catcher’s job unquantified and assumed as zero — this clearly isn’t the case, but there’s also no reason to attempt to quantify what you can’t.
But people are still working on objective measures of catcher defense, and yesterday at Baseball Prospectus, Mike Fast published an excellent study on one aspect: framing. The entire study is worth a read, as it’s extremely well done and very detailed. The crux of the study, though, lies on the idea that framing is a very big deal. Over 150 games, a catcher can potentially save his team up to 35 runs just by making borderline pitches look like strikes instead of balls.
According to Fast’s study, that 35 number belongs to Jose Molina, an unsurprising name to see atop a defensive catchers list. Second place, on a per game basis? That belongs to Lucroy, who has saved the Brewers a shocking 38 runs since coming up in 2010, for a total of 24 runs per 150 games. Throw that into his fWAR, and he’s a 4-win player, roughly an all-star level.
Don’t take these numbers as gospel. Read the study, understand why these numbers make sense. But there’s a reason the Brewers felt comfortable going with Lucroy as their starting catcher in 2010, and it wasn’t because of his offense. They felt excessively confident about his ability as a receiver, and now, we have the numbers to back it up.