For the past two months the Twins have repeatedly insisted that they plan to have Joe Mauer remain at catcher next season despite sitting out the final 40 games following a concussion, but today the team announced that Mauer is moving to first base.
Mauer spent 10 seasons at catcher, hitting .323 with an .873 OPS while making six All-Star teams and winning three batting titles, three Gold Glove awards, five Silver Slugger awards, and one MVP. Among all catchers in baseball history through age 30 he ranks sixth in Wins Above Replacement, behind only Johnny Bench, Gary Carter, Ivan Rodriguez, Joe Torre, and Ted Simmons. Mauer was an amazing all-around catcher.
Back in August when Mauer suffered the concussion I wrote a lengthy article breaking down how a position switch would impact his all-around value. The short version is that big batting averages and on-base percentages would continue to make him a very good-hitting first baseman, but his lack of power would keep him from remaining as elite there as he was at catcher. Instead of being a top-three catcher every season, he projected to be in the 5-10 range among first basemen.
However, at some point this issue became less about value and more about health, and given how he struggled with post-concussion symptoms and given how many catchers spent time on the concussion disabled list this season the move makes sense for both Mauer and the Twins. He needs to be healthy and in the lineup, which is far more likely at first base than catcher.
Minnesota will likely turn to Josmil Pinto as their primary catcher following an impressive September debut, with Ryan Doumit and Chris Herrmann also in the mix to catch.