Gophers left tackle Ben Lauer injured his left knee Sunday during the team’s third practice. Even though it wasn’t said to be serious, it exposed one of the team’s concerns.

Lauer is a 6-7, 317-pound junior who was named a freshman All-America two years ago, but injuries limited him to six starts last year. At right tackle, the Gophers have 6-9, 324-pound junior Jonah Pirsig, who has battled injuries through his college career, too.

The Gophers really hope those two stay healthy, so they can keep 6-5, 310-pound senior Josh Campion at right guard, instead of moving him back to tackle.

With Lauer icing his knee, the Gophers gave 6-6, 310-pound sophomore Alex Mayes and 6-6, 291-pound freshman Quinn Oseland reps at left tackle with the first-team offense Sunday.

“You get guys dinged up, you’re going to have to test your depth pretty quickly,” said Matt Limegrover, the team’s offensive coordinator and offensive line coach.

Oseland is from Springfield (Ill.) Sacred-Heart Griffin and was one of the highest-rated players in this year’s Gophers recruiting class.

“I’m really impressed with Quinn as far as a true freshman kid coming in,” Limegrover said. “He was so well-coached in high school that you can see that carryover. There’s just a naturalness about what he does.”

Mayes’ development at Minnesota has been slowed by a shoulder injury, but Limegrover said he’s fully healthy and no longer has to wear a shoulder harness.

“He doesn’t have any restrictions now, so that’ll help him,” Limegrover said. “And he’s such a good athlete; he’s just got to get back into it. He’s basically been on the shelf for two years.”

Other injuries of note

• Redshirt freshman wide receiver Isaiah Gentry injured his right hamstring during a one-on-one drill with the defensive backs. Gentry also dealt with a hamstring injury during spring practice. The team has high hopes for him if he can stay healthy.

•  Lincoln Plsek, an expected starter at tight end, has been slowed by a back injury early in camp. Brandon Lingen and Nate Wozniak have been getting reps at tight end with the first-string offense.

“We’re going to take it easy with [Plsek],” Limegrover said. “Let these other guys get some reps. We know what Lincoln can do.”

Leidner inconsistent

Mitch Leidner threw several good deep passes in the one-on-one drill between wide receivers and defensive backs. But Leidner threw two interceptions in 11-on-11 action. Safety Damarius Travis had one of the interceptions, and linebacker De’Vondre Campbell had the other.

“He’s had his moments,” Limegrover said of Leidner. “I think there are moments where you go, ‘Yes!’ And there are moment where you go, ‘OK, come on.’

“I think by the time we get within a week or so of TCU [for the Sept. 3 opener], we’re going to have a lot more ‘All rights,’ than we will ‘Ah, geez.’ So that’s the plan, and playing against our defense, they can give everybody headaches.”

Spielman narrows list

J.D. Spielman, a multi-position standout at Eden Prairie, announced on Twitter that he will make his college decision Saturday and narrowed his list to five: Iowa, Iowa State, Michigan, Minnesota and Nebraska.

Spielman is the son of Vikings General Manager Rick Spielman. Eden Prairie linebacker Carter Coughlin has been committed to Minnesota since March and implored Gophers fans on Twitter to let his teammate know how much they want him at the U.

Praising the defense

Limegrover likes what he’s seen — from the Gophers defensive linemen.

“Everybody talks about our secondary, you know [defensive tackles] Steven Richardson and Scott Ekpe — Scott looked like a million bucks today, it’s like he never missed a beat [from last year’s knee surgery].

“It’s terrible to see for me         as an offensive line coach  in camp, but me, wearing the ‘M,’ it’s great to see because he’s going to be a force in there.

“Andrew Stelter — if you see him roaming around, he looks like a different kid, I don’t know how much he weighs [277 pounds, now], but he looks like a Big Ten defensive tackle right now.”