This is what might be going on with Joe Mauer:

The four-time All-Star catcher does not feel as if he's playing with a proper foundation from his legs. This has caused him to try to do the basics - hit and throw - with his upper body and middle of his torso.

In turn, this has caused pain in his shoulders and hips.

Mauer spent more than a month in Fort Myers arriving at 6 a.m. and working out for hours to strengthen his legs and body, before playing in an exhibition game.

There were interruptions in his routine to have injections to lubricate his left knee. There was a cleanup surgery on that knee in the middle of December.

Yet, it isn't a lack of working on his legs and the rest of his body that put Mauer in this predicament. It was the lack of playing games - of being in shape, but not in baseball shape.

This came to a head last week. The Twins were off on Monday, Mauer played Tuesday and manager Ron Gardenhire came to the ballpark for Wednesday's noon game ready to have his catcher in the lineup.

Mauer said he was sore. Gardenhire went with Drew Butera.

The Twins lost to Kansas City, falling to 4-7, and then headed to Tampa Bay. Mauer arrived at Tropicana Field and said he was both sore and feeling ill.

The reading the Twins received from Mauer was that he wouldn't be able to play for three or four days. The manager, presumably frustrated, told General Manager Bill Smith that he needed another catcher.

The Twins put Mauer on the DL and called up Steve Holm. Mauer wound up in the hospital with a virus. Gardenhire talked hopefully on Friday that perhaps it was Mauer being sick, not the previously suggested "bilateral leg weakness,'' that had caused Mauer to complain of soreness.

Mauer stuck a pin in that balloon on Sunday, when he came to the ballpark and told reporters that he didn't think his weakened legs and soreness elsewhere was related to the sickness.

Apparently, the reason for that is Mauer was feeling this weakness and soreness almost from the start of the season - before a virus would have an impact.

Mauer was scheduled to visit his back surgeon at Johns Hopkins on Monday. This was an appointment made much earlier, and simply because Mauer and the Twins were in Baltimore ... not due to whatever is ailing him at the moment.

Unless there's a diagnosis of a clear physical problem, the Twins are in a classic Catch-22.

Going back to Minnesota and spending more time working on his legs does not seem like a solution. He did that for five weeks in Florida, had no complaints at the start of the season, and then started playing full games and here came the weakness, followed by the soreness.

Mauer was in a workout room shape when the Twins left Florida but not in baseball shape because of his light schedule of games and at-bats.

He has to play games to get back over 90 percent, and he doesn't feel as if he can perform close to normal in this condition. Presuming no real physical problem is found at Johns Hopkins or with other doctors in the next few days, here's a guess:

Mauer will not return on April 28 (when he could come off the DL). He'll be gone longer than that, and will need a rehab assignment - probably in Fort Myers - before he's back in the Twins' lineup.