MINNEAPOLIS — Minnesota Twins center fielder Denard Span was out of the lineup for the fifth time in the last six games because of whiplash from a home-plate collision last week. He was diagnosed with a mild concussion and placed on the new seven-day disabled list on Thursday night.

Span spent four hours in the afternoon with a specialist. He hurt his neck Friday, sat out for two days, played Monday but then felt lightheaded and returned to Minnesota for further examination.

Span was bothered two years ago by dizziness caused by an inner-ear condition, and some of those symptoms flared up following the collision. He was told to rest for a few days, for now.

“It comes and goes. It’s not 24-7. Every now and then I’ll feel like spaced out and feel like the room is moving a little bit,” he said.

It’s not clear if he’ll be able to return immediately when he’s eligible to come off the disabled list, which was added this season to help give teams more flexibility with concussed players. Outfielder Rene Tosoni was recalled from Triple-A Rochester to take Span’s place on the roster.

Span was the latest Twins standout to be hurt this season.

The most famous of them all is Joe Mauer, who was catching again for Class A Fort Myers Thursday night. Mauer last played for the Twins April 12, the first year of his $184 million contract so far wrecked by soreness and weakness in his legs and shoulder.

Mauer is eligible to come off the 60-day disabled list on Sunday, but manager Ron Gardenhire pushed for a cautious approach.

“If he’s ready then we’ll be bring him up here, but not until. If he hasn’t caught enough and we don’t deem him ready to do that, then we don’t do that. We saw that out of spring training when we thought he was ready then,” Gardenhire said. “We want to make sure that we give him plenty of time here and plenty of ballgames to where it’s not coming up here, catching a ballgame, sitting out two.”

Mauer has caught only 22 innings between Class A and extended spring training games, and that’s not enough for the manager.

“He wants to play. He’s missed a lot of ballgames. On the flip side of that we have to make sure he’s ready to get back up here,” Gardenhire said. “We have to make sure he can go and catch three, four, five days in a row, and that’s the biggest thing for me.”

Gardenhire said he’d like to see Mauer get some time with Triple-A Rochester, too, as with middle infielder Tsuyoshi Nishioka, who has been out even longer than Mauer due to a broken left leg.

“I don’t want him rushed up here,” the manager said, adding: “My preference is for him to go to Triple-A and play, whatever, three, four more ballgames, just to see how he’s handling himself and make sure he’s on track and make sure he’s ready to step back in here.”

Left-handed reliever Glen Perkins threw a bullpen session before Thursday’s game and will pitch an inning for Rochester Saturday to test his strained right oblique muscle. Right-handed reliever Joe Nathan also threw a bullpen session Thursday and felt great, according to McWane, and will do the same Saturday. If that goes well, he’ll start a rehabilitation assignment with Fort Myers.

First baseman Justin Morneau has fluid in his left wrist, according to an MRI test, but he’s able to keep playing through that “as tolerated,” McWane said. There’s no structural damage.

Also, the Twins determined designated hitter Jim Thome’s strained left quadriceps muscle has stemmed from his chronic back problems. He met with a specialist and will have an epidural shot to relieve the pain. If that works, he’ll move forward with his rehabilitation.