"A catcher and his body are like the outlaw and his horse. He's got to ride that nag till it drops."

-Johnny Bench Catcher.

It's a brutal assignment. A big-league backstop is subject to being battered by foul tips, back-swings and barreling base runners. His glove hand is swollen throughout the season from being pounded by mid-90s fastballs on a nightly basis. And, worst of all, there's the relentless wear-and-tear on his lower body -- the result of crouching and standing up countless times per game for seven straight months.

Given these facts, it should come as no surprise that few players are able to catch regularly throughout an entire season while still producing with the bat. Last year, only two backstops in the major leagues accumulated enough at-bats to qualify for a batting title while posting an OPS north of .700.

Joe Mauer was one of them, of course. During his career, he's usually ranked as the best offensive catcher in the league, and he's also been one of the most durable. This is precisely what makes him so uniquely valuable.

I fully understand how closely Mauer's value is tied to being behind the plate, which is why I've always maintained that the Twins should keep him there until it's no longer reasonable to do so.

I believe we've reached that point.

The final red flag probably should have been Mauer's knee injury last year, which sapped him of his power and reduced him to a non-factor by the time the playoffs rolled around. Oddly, a decision was made two months into the offseason to operate on the knee (the same one that cost him most of his rookie campaign).

Mauer is no stranger to rehabbing from injuries and surgeries, but his return from this particular procedure has been conspicuously different. Two months after the operation, he showed up at spring training "a mess" and, despite multiple lubricant injections and hours spent each day trying to strengthen his legs, he could not work his way into playing shape.

I give the hometown star credit for trying to push through the dead legs and get on the field, eager to justify his enormous new contract, but in the end Mauer's determination probably only set him back. He played poorly over nine regular-season games before landing on the disabled list. Some have speculated he could be gone until the All-Star break or longer, and with the team completely unwilling to divulge any information about the specific nature of his ailment or set a firm timetable for his return, such speculation doesn't even seem particularly irresponsible.

It's true that Mauer provides notably less value while playing a position other than catcher, but he provides no value when he's not on the field. That's a problem that's getting worse, not better, and with the investment this organization has made in Mauer it's one that is becoming less tolerable.

He missed the first month of 2009, and played in even fewer games last year. With only nine games in the books this season and no return in sight, it appears as though he may play less this year than either of the past two.

Not acceptable for a $23 million player.

Throughout his career, Mauer has routinely worn down late in the season. His .439 slugging percentage in September ranks as his lowest outside of April. He's been a non-factor in the playoffs, with one extra-base hit in 39 career postseason plate appearances.

Also not acceptable for a $23 million player.

Will Carroll, a writer who specializes in covering sports injuries for SI.com, wrote the following about Mauer back in March, before he landed on the disabled list less than two weeks into the season:

Over the years, people other than Carroll have pointed to many different factors as justification for moving Mauer out from behind the plate: His 6-foot-5 frame.

His need to sit out about a game per week even when healthy.

Diminished offensive production due to the rigors of catching.

The severe knee injury he suffered during his rookie campaign.

The mounting lower-body injuries and surgeries that have piled up since.

And now, mysterious leg weakness that has the Twins' most valuable asset on the shelf and out of sight indefinitely.

None of these issues in isolation represent compelling reasons to depress Mauer's peak value by changing his position. But, when you look at the big picture, and the amount of money the organization has invested in him over the next eight years, there's one inescapable conclusion:

Mauer has to be moved. And soon.

Johnny Bench, the Hall of Famer quoted at the beginning of this article, caught until he was 33, then switched to first and third base. He kept playing with reduced effectiveness for two more years before retiring at 35. Bench rode that nag as long as he could -- maybe for too long (he required hip replacement surgery at age 57).

With the investment they've made, the Twins can ill afford to keep sending Mauer down that path, especially when his body is screaming out that it's had enough.

By now, the dilemmas being mulled at 1 Twins Way should be where to move Mauer and how to replace him with someone competent behind the dish.