Joe Mauer hasn't done any serious lifting or tough conditioning exercises to get in shape for spring training on orders from his surgeon, after he had kidney surgery at Mayo Clinic on Dec. 22.

Publicly, Twins officials won't admit any concern about the All-Star catcher and two-time American League batting champion being 100 percent healthy in time for the start of the season. But then you keep hearing behind the scenes that there is some worry.

Mauer won the batting title with a .328 average, even though he had serious back pain for the last six weeks of the season. Examinations revealed the former Cretin-Derham Hall star was born with a small abnormality in one of his kidneys, according to Twins physician Dr. John Steubs.

"At the end of the season we were going to just let him rest," Steubs said. "And he rested for two, three, four weeks, and it didn't get better. Then we did the studies that we did and found this problem, and he elected to get that taken care of.

"So, at the time he had this done, we weren't sure that it was the reason for his back pain. The rest of the studies, the rest of the MRI and everything else we did of his back looked just fine, and we found this little abnormality in his kidney."

Steubs said Mauer saw two or three specialists before he had anything done, but the recommendation was that he get this taken care of so it wouldn't be a long-term problem.

"Hopefully it also will clear up any problems he's had with his back," Steubs said. "Because your kidneys sit in the back area there, and we don't know what role this has played in any kind of backaches he's had over the years.

"Joe says he thinks that [the surgery] has corrected that, so it hopefully will take this kind of nuisance back pain out of the loop."

Mauer was scheduled to see his Mayo doctor this past week, and Steubs said 33 players in the organization, including Mauer, will be examined Saturday. Mauer will then find out if he can start doing his normal pre-spring training work.

"I read in the paper, or somebody had mentioned on one of the radio stations that he may not be ready for spring training and the season," Steubs said. "The reality is he had the surgery just before Christmas. We knew it was going to be a month before he could start doing anything more vigorous.

"So he hasn't been really delayed any more than we thought. We thought that he would be probably ready to start doing things again now, and have about three to four weeks before spring training to kind of get some work in. Then we'd gradually work him into full baseball activities over spring training.

"Mauer keeps himself in good shape, so I don't have a worry about him. This is nothing that we didn't expect. We expected him to have some time before the doctor would give him the OK to get going.

"I think that unless something unforeseen comes up, and unless I hear differently when I talk to Joe on Saturday, I think he'll be good to go. He'll have time to work himself into playing shape and get ready."

U needs to win at home

Bob Knight, doing the color commentary on Thursday night's Gophers-Purdue game, said he thought the Gophers lacked patience on offense, one of the reasons they lost to the Boilermakers 70-62 at Williams Arena.

"They took too many three-point shots and didn't hit many of them," Knight said. "This was one of their problems."

You don't win many basketball games when you shoot 28 percent (16-for-58) overall and 16 percent (3-for-19) on three-point shots, while Purdue was shooting 47 percent (22-for-47) from the field and 55 percent (6-for-11) on three-pointers.

However, Knight thought the Gophers were definitely a better team than they showed Thursday night.

"The difference was Purdue had the two best players on the floor [JaJuan Johnson and E'Twaun Moore]," Knight said. Johnson had 19 points and eight rebounds; Moore scored 16 points.

You have to win the home games if you're going to make it to the NCAAs, and this loss didn't help.

Jottings

The word is that length of contract is holding up the Twins' signing of former White Sox third baseman Joe Crede and relief pitcher Eric Gagne. ... Running back Gary Russell and tight end Matt Spaeth didn't get a chance to play in the Insight Bowl with the Gophers against Texas Tech in 2006, Spaeth because of an injury and Russell because of academic problems. Now both get an opportunity to play in a little bigger postseason game -- the Super Bowl -- with the Steelers.

Tyrone Carter, the former Gophers safety, has moved around. He was with the Vikings from 2000 to '02, the Jets in 2003 and was signed by the Steelers as a free agent in 2004 and has been there since. Now he is going to his second Super Bowl with the team. And what a break for running back Mewelde Moore. The Vikings decided not to re-sign him after the 2007 season. Now he winds up in the Super Bowl with the Steelers. ... Tickets for the Super Bowl are $800 this year.

Tom Olson, the sophomore 6-4, 275-pound offensive lineman from Mahtomedi, recently committed to Minnesota. His father, Ed Olson, played for the Gophers from 1980 to 1982 and was captain of the '82 team. Tom's older brother, senior offensive lineman Ed Jr., also has committed to Minnesota.

Kevin Payton, a redshirt junior who was suspended for academic reasons, won't be back with the Gophers basketball team next season. ... Chad Calcaterra, the 6-11 Cloquet sophomore center, recently got a scholarship offer from Auburn.

Jimmy Thompson, the Hayward, Wis., redshirt freshman receiver who decided to leave the Gophers program, has decided to transfer to South Dakota, where he will be coached by Gordy Shaw, the former Gophers offensive line coach.

In his sophomore season at Wisconsin, former Orono star Jon Leuer has seen his role increase dramatically. Leuer is averaging 20.4 minutes, 9.8 points, and 4.4 rebounds per game after averaging only 2.9 points and 1.3 rebounds in 8.6 minutes last year. In Big Ten play, Leuer is averaging 26.7 minutes, 9.8 points, and 6.0 rebounds through six games.

Carlos Gutierrez, whom the Twins selected with the 27th pick in the 2008 MLB draft, will pitch for Puerto Rico in the World Baseball Classic this summer. Gutierrez went 3-1 with a 2.10 ERA in 25.2 innings pitched for Class A Fort Myers last year.

Former Twins second baseman Luis Rivas signed a minor league contract with the Cubs on Tuesday. Rivas played for the Pirates last season and hit .218 with three home runs and 20 RBI in 79 games.

Sid Hartman can be heard weekdays on WCCO AM-830 at 6:40, 7:40 and 8:40 a.m. and on his Podcast once a week at www.startribune.com/sidcast. shartman@startribune.com