Joe Mauer isn't a catcher anymore. He's leaving the gear for some other head-trauma target and taking his game to first base, where, presumably, he'll spend the rest of his career, however long that may be.

This was Mauer's decision. He's 30. During a game in mid-August, he took two blows to the mask, and couldn't play the next day. Or the next. The headaches didn't go away. Noise made his head hurt. So did light. He didn't play for a week, then a month, and then the season was over, and October came and he'd get better, then backslide, then get better again. He'd suffered a concussion as a boy, and guessed he'd endured at least a few that went undiagnosed as a man, but this, there was no playing through this. There was hardly any getting through the day with this.

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Mauer was a born catcher and a self-made catcher. If that makes sense. A person is born wanting to catch, and then becomes one. And Mauer worked to be among the best at it. He became the soul of the Minnesota Twins, and then became a lot of their future payroll (more than a quarter of it in 2013), and the rebar for their new ballpark, in part because he was Joe Mauer, and in part because he was Joe Mauer: All-Star catcher.

So, yeah, this isn't great news for the Twins. It's not even great news for Mauer, who wanted to be a catcher forever. Turned out, he was a catcher for long enough to see his pal and former housemate, first baseman Justin Morneau, suffer through concussions, have his production decline, then be traded to Pittsburgh, leaving first base available for a post-concussed Mauer.

"It's frustrating," Mauer said Monday, "it had to end sooner than I anticipated."

He'd consulted with doctors and specialists. He'd talked it through with Morneau. The professionals told him they were concerned by how long it took him to recover, and that's assuming he is recovered. They told him the next foul ball off his mask could bring the same damage, or worse, and the same recovery time, or longer. He spoke to Twins general manager Terry Ryan in October, and they began to consider a permanent switch to first base, and Ryan left the rest to Mauer.

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"If he decided he wanted to catch," Ryan said, "I'm not sure anybody could stand in his way."

Joe is married. Twin daughters were born in July.

"I'll be a father and a husband a heckuva lot longer than a baseball player," he said. "The decision was easier knowing I have them to worry about."

First base was open. The headaches were less severe. He'd gone long enough being irritable, and dreading the onset of thunder in his head and being powerless against it. He's paid to be a great catcher, and a productive hitter as a catcher, which is rare. The Twins owe him another $115 million over five years. While the expectation was Mauer might not have been a catcher when the final dollar was paid out, he was supposed to get closer than this. No man, not even a catcher, sees this coming, however. Ask David Ross. Ask Mike Matheny. Ask Alex Avila and Sal Perez and Austin Romine and Brian Roberts and, damn, Corey Koskie. Remember Corey Koskie? He was a teammate of Mauer's for a brief time.

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