Posted by ESPN.com's Adam Rittenberg

We've got a new No. 1 team and a lot of shuffling throughout the rankings this week. There's still a lot of uncertainty after the fifth spot, but things should get interesting down the stretch.

1. Ohio State (8-2, 5-1): Surprise, surprise, the Buckeyes are back on top in the Big Ten, a league they've owned this decade. After a blowout win against Penn State, Ohio State only must beat Iowa next week to secure the Big Ten's automatic BCS berth, most likely the Rose Bowl. The Buckeyes come in very confident, while Iowa likely will be without starting quarterback Ricky Stanzi.

2. Iowa (9-1, 5-1): The quest for perfection is over in Iowa City, and the loss to Northwestern came with a cost as Stanzi left the field with a severe right ankle sprain. Iowa can still win the Big Ten with a victory next week, but it has struggled mightily in Columbus and will need big things from redshirt freshman James Vandenberg in his first career start at quarterback.

T-3. Wisconsin (7-2, 4-2): Is there a more under-the-radar 7-2 team than Wisconsin? The Badgers quietly keep winning, though Saturday's game against Indiana got pretty interesting down the stretch. Freshman running back Montee Ball really picked up teammate John Clay (concussion), and the Badgers' ground attack surged yet again. Wisconsin remains in good shape for a 10-2 season.

T-3. Penn State (8-2, 4-2): Because of a soft schedule, Penn State had only two chances for signature wins this season and it failed on both. Despite getting both Iowa and Penn State at Beaver Stadium, the Nittany Lions couldn't generate much offense and endured surprising breakdowns on special teams. Penn State could have seen its chances for a BCS at-large berth vanish after Saturday's poor performance.

5. Northwestern (6-4, 3-3): The Wildcats move up two spots after their first win against a top 10 opponent since 2004. Not much has gone their way this season, but they continue to show unbelievable resolve in overcoming adversity. The defense is playing better each week, and Pat Fitzgerald is finding just enough offense despite injuries to quarterbacks Mike Kafka and now Dan Persa.

6. Michigan State (5-5, 3-3): Mark Dantonio said his team must regain respect in November, and Michigan State took a step in the right direction by pounding Western Michigan. Quarterback Kirk Cousins was brilliant and running back Ashton Leggett answered the bell with four rushing touchdowns. The Spartans now face a critical game at Purdue that could determine whether they reach the postseason.

7. Purdue (4-6, 3-3): What a wild season for Danny Hope's team. The Boilers outplay Oregon on the road, drop close contests to Notre Dame and Northwestern, shock Ohio State, lay an egg against Wisconsin and now rally to beat Michigan. Quarterback Joey Elliott and his teammates are extremely resilient, and they have a very real shot at a bowl game. Purdue can't afford any slip-ups and must beat Michigan State this week.

8. Illinois (3-6, 2-5): The confidence is coming back in Champaign as Illinois notched its second consecutive victory. Ron Zook's defense has come alive, and cornerback Terry Hawthorne and end Clay Nurse led the charge Saturday at Minnesota. It will be tough if quarterback Juice Williams misses extended time, but the Illini have faith they can do the unthinkable and finish .500 after a 1-6 start.

9. Minnesota (5-5, 3-4): A Jekyll-and-Hyde season continued for Tim Brewster's crew, which couldn't sustain the momentum from last week's victory against Michigan State. Minnesota came out completely flat in the first half and found itself in a huge hole against Illinois. The Gophers turned it around after halftime, but they're simply too inconsistent this season. This week's game against South Dakota State is a must win.

10. Indiana (4-6, 1-5): You have to feel for the Hoosiers, who just can't turn the corner like other Big Ten programs have (Northwestern, Purdue, Michigan State) in recent years. Junior quarterback Ben Chappell and sophomore wide receiver Tandon Doss have really impressed me this season, but when you can't consistently run the football or stop the run, you're going to lose games. Indiana needs a miracle this week against Penn State to keep its bowl hopes alive.

11. Michigan (5-5, 1-5): It's a meltdown at Michigan right now, as a team that started 4-0 and had some positive vibes going has totally fallen apart. The Wolverines squandered a 24-10 halftime lead against Purdue and endured more breakdowns from a young and marginal defense. Rich Rodriguez's seat is definitely getting hotter as Michigan needs an upset in the final two weeks to make a bowl game.