Joe Mauer is a great baseball player. I don’t think you’ll have very much difficulty convincing anyone of that. On the season, Mauer has hit ten home runs in just 23 games. He is hitting an insane 1 HR/8 AB so far in 2009. While his season started late because of his recovery from kidney surgery, Mauer is just 41.5 plate appearances away from qualifying for the batting title. (3.1 PA per team game is required in order to be eligible for the award.)
Mauer’s .438/.525/.875 line has pundits scratching their heads. The ten long balls just add to the mystery. With an OPS of 1.400 he easily leads any batter with more than three PA. What is the reason for this incredible stretch? Is it just a hot streak that will soon die, or has Mauer actually “gotten better”?
Tom Tango, co-author of “The Book: Playing the Percentages in Baseball,” suggests 220 plate appearances as the baseline for analyzing a player who is flucuating from his average production. Any amount less than that (Mauer has only 98 PA this year) and you can chaulk the success/regression up to luck and expect a return to the mean production of the player.
Has Mauer been extremely lucky in 2009? I am tempted to think so. Mauer is only 26 years old and is still maturing physically. I would strongly doubt that Mauer is actually doing anything consciously to increase his home run total and that he is simply finding it easier to launch a 400-footer. Will this return to normal? Probably, because pitchers will adjust to how they pitch to this “new” Mauer. Will Mauer’s sudden power return to normal? Probably, but maybe not.
Aaron Gleeman compared Mauer to the Wade Boggs of 1987, when he hit 24 home runs. On average, Boggs rarely had a home run total reaching double digits. Actually, he only reached two digits once again in his career: 1994 with the Yankees.
There is little doubt in my mind that Mauer will not continue to rake opposing pitching at the rate he is currently going. He is on pace for a nearly record-breaking season, but that number should regress towards the mean of Mauer’s career.
Weighted On Base Average, wOBA, is a great way to measure a hitter’s true ability. Very similar to OPS, wOBA is more messy but isn’t simply a combination two already-exsisting statistics. wOBA uses the run values of the most common events in baseball relative to an out, divided by the total number of plate appearances. A very good hitter could expect to have a wBOA approaching .400. Through 45 games in 2009 Mauer’s wOBA is .571.
Will he regress towards his mean? Sure, but that doesn’t mean he will return to the same kind of hitter he was last year. The Mauer of 2008 could very well be lost forever, replaced by a home run-hitting monster with an uncanny ability to get on base.
If Mauer survives the 220 plate appearance plateau without a major hiccup in this hot streak, though, he could very well be the next Mantle-caliber hitter.