ESPN College Football

ANN ARBOR, Mich. (AP) -- Michigan had one of the nation's worst defenses just two years ago.

Now -- at least statistically -- the unit is among the best in college football. The 20th-ranked Wolverines rank fourth against the pass in the country, 10th in total defense and 16th in points allowed.

Since a 41-14 loss to Alabama and a 31-25 win over Air Force, Michigan (5-2, 3-0 Big Ten) has given up fewer than 10 points a game and just 23 points combined in three conference matchups.

"We're feeling more and more confident each week," safety Jordan Kovacs said after beating Michigan State 12-10 on Saturday. "But we don't want to become too comfortable and get complacent."

Brady Hoke will make sure his players stay humble as they head into Saturday night's road matchup with dangerous Nebraska.

Hoke said the defense wasn't near what it needs to be to win a Big Ten championship after shutting down the Spartans, other than on one drive, and helping the Wolverines come out on top in a game without scoring a touchdown for the first time since beating Purdue in 1995.

Two days later, Hoke still wouldn't say how much -- or if -- the defense has improved since its shaky start.

"Let's wait until a year's over," Hoke said Monday. "That's when you're going to know. "

No. 20 Michigan, leaders of the conference's Legends Division, will find out more about its defense Saturday night.

The Cornhuskers (5-2, 2-1) lead the Big Ten in rushing (279.0 yards per game) and scoring (41.6 points) with dual-threat quarterback Taylor Martinez along with running backs Rex Burkhead, who may not play against Michigan because of a knee injury, and Ameer Abdullah.

Abdullah says he is prepared to take over as the featured back again, with Burkhead missing all or part of five games. Coach Bo Pelini said Monday his inclination would be to rest Burkhead at least a week after the senior aggravated a knee injury at Northwestern last week.

"We'll proceed cautiously," Pelini said of Burkhead, who has two 119-yard rushing games this season. "He's a lot better today. He was a lot better yesterday, but even better today."

Nebraska, meanwhile, expects to know more about its offense after facing Michigan.

"They're a really good defense, just like last year," Martinez said. "Hopefully this time we can get them."

Martinez struggled through the air -- 99 of 23 for 122 yards and a TD -- and on the ground -- 16 carries for 49 yards -- last year at Michigan. That helped the Wolverines turn a 10-all game into a 45-17 rout against Nebraska, relying on their senior-laden defensive line.

Martinez didn't struggle against the Wildcats last week, throwing for 342 yards and three touchdowns -- two in final 5:55 to rally the Huskers to a 29-28 victory.

That comeback has put Nebraska in position to take control of the division with a win over Michigan, which will be making its first visit to Lincoln since 1911.

Without defensive linemen such as Mike Martin and Ryan Van Bergen back this year, some thought Michigan might struggle up front. Early on, the Wolverines did while getting pushed around by the Crimson Tide in the opener and looking a step slow the next week against Air Force.

Will Campbell said he and his teammates on defense have turned around their production by preparing better and helping each other swarm to whomever has the ball.

"How we run to the ball, that's what's making this defense good," Campbell said.

Coaching is helping too.

Hoke is a defensive-minded coach, who spend a lot of time with the defensive line each practice, and he's got one of the best in the business leading the unit. When Rich Rodriguez was fired and Hoke was hired following the 2010 season, Hoke successful recruited Baltimore Ravens defensive coordinator Greg Mattison to leave the NFL and return to Ann Arbor, where he was an assistant from 1992-1996.

"For him to leave a defense like the Ravens -- with guys like Ed Reed and Ray Lewis that I looked up to -- and to come back to Michigan, shows you how much this program means to him," safety Thomas Gordon said. "And, it showed us that he wanted to come back and get this defense, and most importantly the program, going in the right direction."