Scouting Illinois quarterback Nathan Scheelhaase

Michigan's biggest issue on defense Saturday will be the same thing that has plagued the Wolverines' opponents all year -- how to defend the mobile quarterback.

While Illinois quarterback Nathan Scheelhaase doesn't have the speed Michigan quarterback Denard Robinson does, he is one of the Big Ten's most versatile signal-callers. Like Robinson, opponents have to worry continuously about him pulling the ball down and trying to make plays as a rusher -- more so than as a passer.

"Scheelhaase is a really versatile quarterback," Michigan defensive lineman Ryan Van Bergen said. "Looking at some of the numbers this year, he's become a better passer, and he's going to be more difficult to defend than he was last year.

"The thing about him is that everybody realizes his feet and what he does this year that doesn't resemble last year is he moves his feet not necessarily to run but to still look downfield to make plays. So we have to be aggressive and keep attacking when we're rushing the passer."

Scheelhaase -- Illinois' leading rusher in carries and yards -- has 501 yards this season running and 1,687 yards passing through nine games. As a redshirt freshman last season, he ran for 868 yards and threw for 1,825 yards.

So he should surpass his passing totals and might equal his rushing totals in 2011.

"The quarterback is throwing the ball well," Michigan coach Brady Hoke said. "He's improved that part. Not that I watched him a lot a year ago, but I think he's throwing the ball pretty well."