Among a slew of nagging injuries to members of the Michigan football team, the one to junior left guard Ricky Barnum appears to have the most ramifications for its game against Minnesota.

Barnum twisted an ankle last week against San Diego State and did not practice with the team Tuesday. Coach Brady Hoke said Wednesday he was unsure whether he'd practice later that afternoon.

"(But) I'm not saying he's out (for Saturday)," Hoke said. "He's trying to take care of that ankle."

No. 19 Michigan (4-0) opens Big Ten play against Minnesota on Saturday (noon, BTN).

If Barnum can't play, sophomore Michael Schofield likely would replace him. Schofield was called upon when Barnum went down against the Aztecs, and also started in Week 1 when Barnum did not dress due to "team issues."

Schofield has played well across the line, and coaches rave about his versatility. He actually is listed as the backup at left tackle, but plays guard as well.

"Mike Schofield is a guy who's been here and he's been working hard since he's been here, and he has a grasp of what he's doing," junior right guard Patrick Omameh said. "We feel comfortable with him in the game."

Barnum's injury is a blow to a position group that already is thin. Michigan has only eight scholarship offensive linemen, and Hoke is concerned about his depth there.

"It affects you in practice," he said. "Guys you've got to bring up, on both sides of the ball, guys who might be fighting for two and three in there when you are down, they've got to go over.

"You take a good look from your look teams. That's one reason we do so much against each other. We started doing that when I went to Ball State because of the competitive nature of going one-on-one, twos-on-twos, the speed, all those things."

In other injury news:

• Cam Gordon: The sophomore linebacker has yet to play this year because of a balky back, but Hoke said he is improving. "He is just working himself back into it. He did some good things (Monday). I think he feels better." Hoke also said Gordon was improving last week and would be available, but then he did not dress.

• Brandon Herron: The senior linebacker hasn't played since he scored two touchdowns in the opener because of a leg injury, but Hoke said he is finally "100 percent." Where he'll fit into the rotation on the weak-side, though, is unclear. Starter Brandin Hawthorne has emerged as one of Michigan's best defensive players and freshman Desmond Morgan also has seen time. Both of those players are listed above Herron on the depth chart.

• Troy Woolfolk: The senior cornerback did not play in the second half against San Diego State after leaving early due to a left ankle injury. Hoke said he has done everything he normally would do at this point in the week.

Regardless of injuries, the physicality of practices has yet to be tapered.

"Not right yet," Hoke said. "As you get into the marathon that a season is, you may lighten up a little bit later, but this isn't the time for us to do that.

"We had a very good practice (Tuesday), on both sides of the ball. We had a lot of energy. I thought it was physical, and how we want to be physical in the course of competing against each other."

Tailback committee taking shape

Hoke affirmed offensive coordinator Al Borges' opinion that, at this point, he doesn't care as much about using a tailback-by-committee approach as long as a couple guys are netting more than a 100 yards combined.

"I’m fine with that," Hoke said. "And, again, I go back to the statistic that counts: Winning.”

Hoke and Borges had said throughout the pre-season they preferred to find a lead back. Of course, they sort of have one in quarterback Denard Robinson.

“You could say that, probably," Hoke said. "He carries the ball, I know that. But I don’t know if I’d consider him a back, personally.”

No word on Hayes redshirt

When asked if freshman running back Justice Hayes would receive a redshirt this season, Hoke said he "wouldn't say that yet."

Hayes has yet to see game action this season, and did not dress last week against San Diego State due to an undisclosed injury that Hoke described only as "a bump."

In addition, Hoke said he's not sure whether there are any current freshmen that have not played but could still see game time.

"I hate to count anybody out, because you never know," he said. "You get guys twisted up or those kind of things, so you never know."

Nickel back not set

Michigan has used both freshman cornerback Raymon Taylor and sophomore safety Thomas Gordon as the fifth member of its nickel package over the past two weeks.

Hoke said both players have seen time there because neither has stepped up enough to take the job.

"We'll use both," Hoke said. "Raymon's a young guy who's learning and Thomas is more of a veteran, obviously. But we'll use both guys. They both are doing OK. Not quite what we need."

Nick Baumgardner contributed to this report. Kyle Meinke covers Michigan football for AnnArbor.com. He can be reached at 734-623-2588, by email at kylemeinke@annarbor.com and followed on Twitter @kmeinke.