The identity of the Michigan Wolverines football offense is based on running the football, then doing everything else. The Maize and Blue can air it out, with a 60.4 completion percentage and an average of 194 passing yards per game, but they've shown that, if possible, they'll lean on their physical offensive line and two-headed monster at running back.

Redshirt sophomore running back Hassan Haskins has rushed for 492 yards and eight touchdowns on 101 carries, while second-year freshman Blake Corum has accumulated 607 yards and eight touchdowns on 97 attempts.

There are many ways to travel, head coach Jim Harbaugh has said, but the ground game is the Wolverines' preferred method.

Only nine teams have thrown fewer pass attempts per game than the Wolverines, who average 22.3, and only 15 squads have rushed more per contest (45.2 attempts). Harbaugh and Co. have made it clear that they're going to do what works, and running the ball has. Michigan has compiled more than 100 rushing yards in all six games, 200-plus in four tilts and better than 300 in three contests. The Wolverines rank seventh nationally with 246.5 rushing yards per game.

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That leads us to an intriguing matchup with Northwestern in Ann Arbor this coming weekend. The Wildcats' defense has been porous against the run, yielding 205.7 yards per game on the ground, a mark that ranks 117th in the country.

Here are Northwestern's run defense numbers in its six games:

• Michigan State: 326 yards and four touchdowns on 37 attempts

• Indiana State: 31 yards on 22 attempts

• Duke: 208 yards and two touchdowns on 53 attempts

• Ohio: 179 yards and one touchdown on 31 attempts

• Nebraska: 427 yards and seven touchdowns on 53 attempts

• Rutgers: 63 yards on 34 attempts

While it's possible that the Wildcats have fixed their struggles heading into this clash, after stymieing Rutgers' run game, even head coach Pat Fitzgerald admitted earlier in the week that facing the Wolverines is a different level of challenge.

Is this another prime opportunity for the Maize and Blue to pound the rock and beat another team into submission?

With Michigan beginning the year with three straight 300-plus rushing yard games and continued success the following three contests, many have wondered just how good the defenses they ran through were. Through seven weeks of the season, let's take a look at how they've fared overall, with a more significant sample size perhaps revealing just how impressive the U-M ground game's feats have been.

As expected, Michigan largely performed much better against the defenses that have struggled against other teams as well, but was still able to muster up adequate rushing games against the stouter teams (Wisconsin and Nebraska).

Michigan racked up more than 300 yards against both teams that rank 90th or worse in run defense, over 200 yards against 60th-ranked Nebraska and still had success against the others (including WMU, whose No. 29 ranking may be inflated due to a MAC schedule). And if the first six games have told us anything, Michigan will pound the rock with much success against the Wildcats.

1-8 Is Fitzgerald's record against Michigan since taking over as Northwestern's head coach in 2006. His lone win occurred in Ann Arbor in 2008, when his Wildcats took down Rich Rodriguez's Wolverines, 21-14.

2 Sacks allowed for the Michigan offense, with that mark ranking second in the country. The Wolverines lead the nation with just 13 tackles allowed behind the line of scrimmage. Both stats lead the Big Ten.

5 Of the last seven meetings between the two schools have ended in one-possession games, with the other two being lopsided in Michigan's favor. The Maize and Blue have come out on top in each of the last six meetings.

9th In the country in scoring defense for the Wolverines, who are allowing just 15.5 points per game. The Maize and Blue rank 14th in scoring offense (38.5 points per outing).

10.5 Tackles per game for Northwestern fifth-year senior linebacker Chris Bergin, a Bloomfield Hills, Mich., native. He's totaled 63 stops in six contests, with that average topping the Big Ten.

17.6 Yards per attempt on passes that traveled 20 yards or more in the air for Michigan redshirt freshman quarterback Cade McNamara. That mark ranks 19th nationally among signal-callers who have thrown 10 or more such passes, according to PFF. On those balls, McNamara has completed 8 of 20 for 352 yards with four touchdowns and no interceptions.

37 Inches is how tall the George Jewett Trophy stands. Saturday's game will be the inaugural matchup for the prize, which is the first rivalry game trophy named for an African-American Player in FBS history. Jewett was the first African-American to play football at each institution and the Big Ten. He played for U-M during the 1890 and 1892 seasons, then left for Northwestern in 1893 to finish his medical degree, competing for the Wildcats for two seasons on the gridiron.

61 Points for junior kicker Jake Moody (leads the team), who has nailed 12 of his 13 field goal attempts and slots ninth nationally in scoring average (10.2 points per game). He has also generated 37 touchbacks on 45 kickoffs, yielding just 35 kickoff return yards total this season, which ranks second in the country.

80th-Or-Lower is where Northwestern ranks nationally in five major statistical categories: 83rd in total offense, 93rd in total defense, 95th in passing offense, 110th in scoring offense and 117th in rushing defense.

93.7 Rushing yards per game for Northwestern sophomore running back Evan Hull, checking in at fifth in the Big Ten. His 5.9 yards per carry slot seventh in the league.

1993-96 Is when Fitzgerald was a linebacker at Northwestern. Also a former player at the school he coaches, Harbaugh will have gone up against five different coaches who played at the program they now work for in his team's first seven games.

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