Joe Mauer, First-Tier First Baseman

One of the most remarkable things about the Internet is the speed with which news finds its way to updated Wikipedia pages. Even during the MLB playoffs, you can usually find notes about player achievements or umpire errors within a matter of minutes. MLB.com does not operate like Wikipedia, in that not just anyone can go in and change things around. But there is one similarity, in that here’s a screenshot of part of the Twins’ official roster from earlier Monday:

Somebody’s conspicuously absent. Let’s scroll down just a bit:

Monday, the Twins announced that Joe Mauer will be transitioning from catcher to first base full-time. The statement is effective immediately, and it took no time at all for the Twins’ site to update itself, with Mauer joining a new group of peers. Depending on how you feel about Josmil Pinto, the Twins are now in real need of finding some help behind the plate, but this isn’t a decision founded upon short-term team need. This is a blend, of what’s best for the Twins, and of what’s best for Joe Mauer.

Mauer, as you can see right there, is officially 6-foot-5. This puts him in a tie for the tallest catcher in big-league history, and for that reason there’s been talk of him not remaining behind the plate since before he even got drafted. Many have expressed skepticism that tall catchers can deal with the physical responsibilities and rigors of catching, and Mauer himself has been through his share of injury scares. Now he’s moving permanently before his 31st birthday. But Mauer has caught 8,000 innings in the majors. He remained a catcher for a while, and he was a pretty good one. This is less validation for skeptics, and more a response to a concussion that could’ve happened to anybody.

Just for fun, here’s a Mauer note from 2001:

“And he should stay behind the plate for a long time. But if he ever moves to first base, he’s a Gold Glove first baseman. That’s how talented he is.”

Joe Sheehan touched on the possibility of Mauer moving back in 2004. There was always a chance. Mauer did well to put it off for this long. Had it not been for some foul tips this past summer, Mauer would probably be preparing to catch another full season. As is, Mauer and the Twins are being simultaneously reactive and proactive.

When Mauer was diagnosed with a concussion, the Twins talked about the chance that he’d have to move. He does have an additional track record of some lower-body problems, so it’s not like the concussion was the first blemish. What led to this decision:

Mauer, a six-time All-Star as a catcher, decided to make the change after consulting with doctors from both the team and the Mayo Clinic. It’s a change from his earlier stance, as he maintained at the end of the season that he wanted to remain behind the plate.

But after weighing the risks, Mauer, who is currently symptom-free from the concussion, determined that it would be in the best interests of both him and the Twins for a position change.

From just a life-wellness perspective, there’s a reduced concussion risk at first base, so Mauer won’t have to worry so much about his brain. Which, in turn, means he won’t have to worry so much about his ability to live a normal life following the conclusion of his playing career. To say nothing of the benefits for his knees and back. You can still get yourself hurt anywhere at any position, but it’s fair for Mauer to think about the next 50 years of his life, instead of just the next five.

And from a baseball perspective, this goes beyond just pointing out the position adjustment between catcher and first. Obviously, a catcher who can hit like Mauer is more valuable than a first baseman who can hit like Mauer. Catchers who can hit like Mauer was incredibly rare. But that, in effect, is looking backwards. Mauer has accrued a lot of his career value to date from catching. That’s no longer what’s pertinent. Mauer has five years left on his long-term contract in Minnesota, and the question is whether Mauer projects better as a first baseman or as a backstop. Better in terms of ability, better in terms of performance, and better in terms of health.

History doesn’t tell us a whole lot — over the past 50 years, only Mike Napoli and Scott Hatteberg have transitioned from regular catchers to first basemen between consecutive seasons in the bigs. Both, for whatever it’s worth, hit better in their first seasons. Both looked excellent at first base according to UZR. The history is sufficiently limited, though, that we’ll have to try to figure this out just based on what Mauer has done.

We know he’s had some issues staying on the field, and he’s not getting younger, so if Mauer were to remain a catcher, you’d have to project him for less playing time than he’d get as a first baseman. Now, nothing’s been wrong with his bat. He just posted a 144 wRC+, a year after posting a 139 wRC+. Over the last three years, Mauer ranks fifth in baseball in OBP, between David Ortiz and Prince Fielder. It’s hard to imagine that giving up catching could help Mauer hit even more, since it seems like he’s just about maximized his skillset, but it’s perfectly reasonable to suggest Mauer might not decline so fast playing another, easier position. As a catcher, maybe he’d lose some of his ability to square the ball up and hit it on a line. He’d probably be playing through a lot more discomfort. Moving to first might make Mauer’s offensive projection not so much better as less worse over time.

Defensively, you’d think that Mauer should be just fine. He’s already gained some experience at first, doing well over 500 innings. Being a recent catcher, he possesses a broader defensive skillset than most first basemen, and now he’ll be able to practice without having to worry about all the extra responsibilities that come along with being a backstop. Mauer won’t have to go over game plans, he won’t have to study opposing hitters, he won’t have to catch bullpens or give signs or perfect pitch sequences. Playing first isn’t easy, but catching poses the greatest challenge. Mauer should make an easy defensive transition, and shedding those extra responsibilities could also help his bat a little.

The argument has always been that Joe Mauer is more valuable as a catcher than as a first baseman. Through 2013, Mauer and the Twins always agreed. They were, presumably, always right. But the future isn’t the past, and now Mauer’s older, with a concussion on his record and a decline phase to think about. A position change should keep him on the field, and in theory it should help him sustain his level of performance, given that he’ll have to worry about less. By position-adjustment alone, moving reduces Mauer’s value rather considerably. This is offset, in part, by differences in projected games played. This is offset, in part, by differences in projected wOBA. And this is offset, in part, by Mauer just not wanting to risk another brain injury. Maybe you could say they’re all being a little too cautious in moving Mauer now, after one accident. But you only get one brain, and Mauer’s pretty fond of the one that he’s got. A win here and there is hardly what’s really important.