MADISON, Wis. -- No. 15 Wisconsin (4-1, 2-0) will be without their best pass rushing defensive end when they take on No. 12 Michigan (5-1, 3-0) on Saturday in Ann Arbor.

Loudermilk, who was seen in a walking boot on Wednesday, has been ruled out for Saturday's contest.

The redshirt sophomore missed the season opener with a leg injury suffered in spring practice. In four games, Loudermilk tallied six tackles, one for loss, and a pass break up.

In Loudermilk's place, UW is expected to use redshirt freshman Matt Henningsen, a former walk-on, and junior David Pfaff, who saw significant snaps last week against Nebraska.

Freshman safety Travian Blaylock, junior running back Bradrick Shaw, and sophomore linebacker Griffin Grady have also been ruled out.

Two of Wisconsin's three starting cornerbacks are game-time decisions.

Wisconsin listed both redshirt freshman Deron Harrell (upper body) and sophomore Caesar Williams (leg) as questionable. Williams missed the Nebraska win entirely, while Harrell was hurt in the second quarter and did not return.

Defensive coordinator Jim Leonhard didn't expect to know their status until Saturday night.

"It's still early. We're still pushing them, trying to just find out -- obviously injuries, a lot of it goes with rest," he explained Wednesday. "You've gotta get them healthy that way, but you have to kind of test them throughout the week. In my mind, it's a little too early to really say about anybody health-wise. They've all been able to do a little bit.

"A lot of them are probably going to be game-time decisions."

True freshman Rachad Wildgoose Jr., who recorded two tackles against the Huskers, is expected to be available in reserve. UW could also turn to fellow true freshman Donte Burton on Saturday as well.

Wisconsin will also be without starting safety Scott Nelson for the first half. The redshirt freshman was ejected last Saturday for a targeting penalty, and by rule, will have two watch the first two quarters from the locker room.

"He's done a great job of communicating for us," said Leonhard. "He's done a great job of getting guys lined up. He's been productive. He's made plays for us. Missing that playmaking ability this first half is going to be rough, but it's next man up."

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Sophomore safety Eric Burrell will start in Nelson's spot.

Junior linebacker Andrew Van Ginkel (ankle) is also questionable, but has played in UW's last two games after being injured against BYU.

Michigan and Wisconsin kick off at 6:30 p.m. CST from Ann Arbor.