The start of Big Ten Conference play had the usual array of highlights, miscues, excitements, disappointments and, most notably, surprises.

Six undefeated teams started last weekend's matchups, but only four will enter week two of the conference season, including a head-to-head battle of two undefeated teams when Michigan State visits Wisconsin.

The Spartans are the only team yet to play a conference game, and MSU will look to prove the strength of its 4-0 record Saturday.

"This will define [the season]," Michigan State head coach Mark Dantonio said. "We may be underdogs for a lot of people, but our players know they're expected to win."

Confidence sets the tone for a game before the coin is even flipped. After starting the season with two losses, Michigan has strung together two wins, including upsetting then-No. 10 Penn State last weekend. Replacement quarterback Ryan Mallett stepped up his performance to effectively rekindle a spark in Michigan's offense.

"[Mallet] did the things he needs to do," Wolverine head coach Lloyd Carr said. "He executed extremely well."

Michigan starting quarterback Chad Henne has been cleared to play this weekend against Northwestern, but a doctor's note alone won't put Henne back in the driver's seat of the Wolverines’ offense.

"The doctors will leave [playing Saturday] up to Chad, how he feels, and of course, it will depend on what I see and what I think," Carr said. "We want to make sure that when he comes back that his mobility is there. … We're not going to do anything that's going to jeopardize Chad and his ability to react to the pressure that comes with the position."

Injuries, unfortunately, are an unavoidable burden to any team or player. Iowa head coach Kirk Ferentz has had to rewrite his depth chart numerous times already this season due to injury and suspension. Imposing an earlier curfew — a step he took earlier this season — has cleaned up the athletes' night lives, but there is little he can do to ensure a healthy starting lineup.

An already injured Iowa lineup made its way to Madison Saturday, but the Hawkeyes left with even longer list on the injury report.

Junior tight end Tony Moeaki will miss the next few weeks of action for Iowa after he dislocated his elbow and broke a bone in his hand on Saturday. Moeaki was joined by wide receiver Andy Brodell on the injury report. But while Moeaki will probably return in a few weeks, Brodell will likely miss the entire remaining season after suffering a torn hamstring.

Returning home after a brief road trip in which his team went 0-2, Ferentz is happy to be back among the Hawkeye faithful.

"It feels good to be home," Ferentz said. "It's going to be a heck of a challenge for our football team, one, getting off the mat, and secondly preparing for a very, very good [Indiana team]."

Indiana crosses into Iowa territory this weekend after suffering a loss to Illinois last weekend.

"It's been a couple of days since the game, I've had a chance to review it and get on with Iowa," Indiana head coach Bill Lynch said. "We're anxious to get going here, practice and get ready for a typically good, tough, hard-nosed Iowa football team."

Lynch is most worried about the Hawkeye defense, including defensive lineman Mitch King.

"[King] is really an active player. He's really good," Lynch said. "He didn't play against us last year … but he is a player."

The Iowa fans, 70, 000 strong, are part of the atmosphere Lynch wants for his team and for the college game in general.

"It's 70,000 loud fans in a really tight stadium. The fans are right on top of you," Lynch said. "It is a great college environment."

Injuries are a severe blow to a team's confidence on and off the field, but losing a close game has similar effects.

Penn State Coach Joe Paterno took all the blame for his team’s 14-9 loss to Michigan, causing a fall from No. 10 to No. 21 in the Associated Press poll.

"When you lose a game like that, you can only point the finger at one person. You've got to point at the head coach," Paterno said. "It starts with me. I have to get across to the kids that we're going to get better, and we are going to get better."

Penn State will look to for that motivation on Saturday when the team takes on Illinois.