Big Ten power rankings: Week 4

There's a new team at the top.

Ohio State might have needed a fourth-quarter rally to outlast Cal in Columbus, but the Buckeyes remain unbeaten. And with Michigan State's offense flat-lining against Notre Dame on its home field, the Buckeyes move up to the No. 1 spot in the rankings.

Week 3 wasn't as disastrous for the Big Ten as its predecessor, but the league once again didn't flex its muscles and endured some sobering results. Only three unbeaten teams remain in the league -- Ohio State, Northwestern and Minnesota -- and while several teams have suffered losses to very good opponents, Purdue's narrow setback at Notre Dame and possibly Nebraska's loss at UCLA are the only defeats that really hold up in the court of public opinion.

There's not a ton of shuffling among the first six teams, which are all fairly close. Wisconsin looked terrible again, even in victory, and paid the price in the rankings.

The exciting news for Big Ten fans is the league lacks much separation from top to bottom, which should make for some fun division races. Three weeks into the season, these rankings are a snapshot of how teams are playing at the moment.

Let's get to the rundown ...

1. Ohio State (3-0, last week: 2): The Buckeyes had plenty of tense moments Saturday, but star quarterback Braxton Miller came to the rescue in the fourth quarter. Miller has put himself on the Heisman Trophy radar with brilliant performances in the new offense, and some weapons are beginning to emerge around him, namely wideout Devin Smith. Ohio State's defense isn't playing nearly as well as many thought, however, and the Buckeyes won't stay here too long if they allow more than 500 yards again.

2. Michigan (2-1, last week: 3): The UMass game provided few revelations about the Wolverines, who took care of business and steamrolled a feeble opponent. Eight different Wolverines players scored touchdowns in the 63-13 romp, including standout left tackle Taylor Lewan. It was a stress-free day at the Big House, but Michigan needs to get serious again as it prepares to face Notre Dame in South Bend. The Irish should be geared up after dropping the past three games to Michigan, all contests Notre Dame felt it should have won. Denard Robinson owns Notre Dame and likely needs another spectacular effort this coming Saturday.

3. Michigan State (2-1, last week: 1): Coach Mark Dantonio called Saturday night's game a defining moment for his team, and Michigan State learned it has a long way to go to reach its top goal of the Rose Bowl. The Spartans never seized momentum on either side of the ball and had few true highlights in a convincing loss to Notre Dame. Their defense should be fine in the long run, but Dantonio indicated some changes could be coming on offense after poor protection and dropped passes led to Michigan State's first touchdown-less performance at home since 1991.

4. Nebraska (2-1, last week: 4): It's hard to know what to make of these Huskers, who have looked very good at home against weak competition and shaky on the road against a UCLA team that could turn out to be much better than expected. For now, Big Red retains the No. 4 spot. Nebraska might have the most offensive weapons in the Big Ten, and it had little trouble racking up points (42) and yards (527) despite playing without top back Rex Burkhead for the second consecutive game. The Huskers' defense needs to build on a solid effort, and Taylor Martinez must take better care of the ball as Big Ten play inches closer.

5. Northwestern (3-0, last week: 5): Name the only FBS team to have beaten three major-conference foes in the first three weeks. It's Northwestern, which added an ACC notch (Boston College) to a belt that already includes teams from the SEC (Vanderbilt) and Big East (Syracuse). Pat Fitzgerald's team once again won in atypical fashion Saturday, grinding out the game on the ground, playing stout defense and struggling to translate yards into points. Northwestern has a lot to improve and a quarterback situation to sort out, but this young team has to feel very good about its progress through three weeks. The upcoming schedule remains favorable for NU.

6. Purdue (2-1, last week: 6): We're tempted to put the Boilers higher, and Danny Hope's squad looks like the best postseason-eligible team in the wide-open Leaders Division. Purdue definitely has the defense to go a long way this season, perhaps all the way to Pasadena for the first time since the 2000 season. The Boilers also have several weapons in the backfield, as they showcased Saturday against Eastern Michigan. Quarterback play continues to be a question mark, but Purdue is a team to watch the rest of the fall.

7. Minnesota (3-0, last week: 8): The Gophers showed Saturday against Western Michigan that they're more than a one-man team, as they rallied for a nice win despite losing starting quarterback MarQueis Gray. Max Shortell stepped in under center and fired three touchdown passes as Minnesota held off Western Michigan. The concern is how long Minnesota survives without Gray, who likely will miss the next few games with a high ankle sprain. Minnesota's defense should get a good test this week as quarterback Ryan Nassib and Syracuse visit TCF Bank Stadium.

8. Illinois (2-1, last week: 9): Much like Nebraska, Illinois has looked good on its home field and not so good in its only trip away from Champaign. Saturday's win against Charleston Southern showed very little about the Illini, and defending WAC champion Louisiana Tech should provide a better gauge this week. The problem Saturday was the injury bug, as Illinois played without or lost a host of key players. Top quarterback Nathan Scheelhaase should return this week, and Illinois hopes to get some of its other banged-up regulars back in the fold.

9. Iowa (2-1, last week: 10): The Hawkeyes rediscovered the end zone Saturday, thanks to walk-on fullback Mark Weisman, the latest Iowa back to step up after AIRBHG struck again. There's no need to get too giddy about a win against Northern Iowa, but the Hawkeyes controlled the line of scrimmage and the football, and limited their mistakes. Iowa's defense has looked solid so far, particularly against the run, and if the offense can build on this and survive the depth problems in the backfield, the Hawkeyes could soon rise up the rankings.

10. Penn State (1-2, last week: 11): As we've written previously, Bill O'Brien's Lions did some good things in the first two weeks, and they finally put it together in an easy win against Navy. While this isn't a typical Midshipmen team, Penn State's passing attack clearly has made strides under O'Brien as Matt McGloin and Allen Robinson continue to connect for touchdowns. Penn State received another strong defensive effort and finally got a chance to celebrate. It's important that the Lions keep the pedal down this week against Temple, which looks for its first win at Beaver Stadium.

11. Wisconsin (2-1, last week: 7): The Coaches' Poll voters continue to embarrass themselves by putting Wisconsin in the Top 25. We're not nearly as kind to a team that has looked thoroughly unimpressive for most of the first three games. Wisconsin should have lost Saturday night to a plucky Utah State team, and the Badgers were extremely fortunate to walk off of their home field -- a place where they've dominated for years and years -- with a two-point win. The offensive problems go deeper than replacing one assistant coach, and Bret Bielema and his team have some serious work to do. There's a major identity crisis in Madison right now.

12. Indiana (2-1, last week: 12): The Hoosiers showed some grit in the final minutes Saturday night and nearly recorded a nice comeback win behind third-string quarterback Nate Sudfeld. Unfortunately, IU's defense still isn't up to snuff and Ball State had the ball last and capitalized. Indiana certainly has firepower on offense and a much improved passing attack (423 yards, four touchdowns on Saturday), but it's the same old story with the Hoosiers' defense. IU couldn't keep Ball State off the field enough, which doesn't bode well as Big Ten play gets closer.