He’s built more like a refrigerator than a normal human being. That’s how Wisconsin likes him. After all, the Badgers didn’t mind lining up their 6-foot-1, 255-pound behemoth across from defenses 287 times during his sophomore season.

At the Big Ten media days in August, Wisconsin running back John Clay answered repeated questions of whether he was taking too much of a beating. Could he wear down?

All of those carries weren’t for naught — the junior ran for more than 1,500 yards and scored 18 touchdowns that year for the Badgers (9-1 overall, 5-1 Big Ten). He then spent time in the offseason recovering from surgery on both of his ankles.

Clay — the 2009 Big Ten Offensive Player of the Year — is uncertain for Saturday as he is still recovering from a sprained knee suffered two weeks ago.

He's still listed as the starter, but he now has two young hot shots nipping at his heels and vying for carries in freshman James White and sophomore Montee Ball.

White could be described as the speed to Clay’s bruiser. And Ball is somewhere between the two.

The sixth-ranked Badgers’ plan has always been simple: find the biggest, strongest offensive linemen, get a great running back and pound the ball.

“It all starts with their running game,” Michigan coach Rich Rodriguez said on Monday. “They’ll come downhill at you. They’re very big up front. They’ve got big backs, big tight ends. They’ll pound you and do a great job blocking on the perimeter with their wideouts. So you’ve got to be able to stop that. I think everything comes off of that — their bootlegs, their play-action passes and all that start when they can run the ball effectively. When they can do that, they’ve been good against everybody they’ve played.”

Wisconsin’s offensive line is considered one of the best in the country, anchored by a senior left side of tackle Gabe Carimi, John Moffitt and Bill Nagy, with Carimi the most heralded of the group. He was an All-Big Ten performer last year and was on everyone’s preseason All-American list in 2010.

“I love watching, when we’re breaking down film, watching the Wisconsin games,” fifth-year senior guard Steve Schilling said. “They’ve always got great offensive linemen. If you ever watch the other defenses go against them, it helps me. Especially watching Carimi and Moffitt on the left side, (they’re) two of the best in the nation at their positions. So I think I’m going to watch them.”

Last week against Indiana, that line paved the way for a huge day. The Badger offense scored on every single offensive possession, notching 83 points. White and Ball combined to run for more than 300 yards and five touchdowns while Clay sat out with an injury.

The Wolverines (7-3, 3-3) have been gashed for 164 yards per game and Clay, combined with Bell and Montee, could pose problems for the home team’s defense. But the team is coming off of its best defensive performance of the season, a 27-16 win over Purdue last Saturday in West Lafayette.

Michigan held its opponent to fewer than 20 points for the second time this season while playing without two of their best defensive players: junior nose guard Mike Martin (ankles) and senior linebacker Jonas Mouton (chest muscle). Martin fully participated in practice on Wednesday and Mouton was limited. Rodriguez said he was “hopeful” they would return against Wisconsin and both players were listed as "probable" on Thursday's injury report.

Martin and Mouton sure would help in defending the run. It will be key for Michigan to get off blocks and make tackles on the Badger’s running backs — the Wolverines will have to match Wisconsin’s physical play.

“If they want to come out and play hard-nosed football and run up the middle, we’re just going to have to man up and just play with them,” senior cornerback James Rogers said.

In recent weeks, the Wolverines have swarmed to the football and stopped opponents quickly even if the runner broke the initial tackle. Younger players have stepped into starting roles and shown energy, too. Junior linebacker J.B. Fitzgerald, redshirt sophomore linebacker Kenny Demens and freshman safety Ray Vinopal haven’t been afraid to stick their noses around the ball.

But tackling Clay isn’t fun for anyone.

He has rushed for 929 yards and 13 touchdowns this season. White has scored 11 touchdowns and averages nearly seven yards per carry.