The opening argument for the defense earned rave reviews at Notre Dame.

The Irish held Purdue to just one touchdown in a 23-12 win on Saturday in head coach Brian Kelly's debut. That was a refreshing change of pace from the Charlie Weis era, when the defense regularly got torched.

But this week's opponent brings a whole new set of challenges, namely from the guy with the untied shoelaces. Michigan quarterback Denard Robinson looked like a force of nature in the Wolverines' 30-10 win over Connecticut, and Notre Dame will have its hands full trying to slow him down.

Kelly has seen this before; he coached against Rich Rodriguez when Rodriguez was at West Virginia and running the same offense (Kelly's Cincinnati team lost to the Mountaineers in 2007). So, he knows what's coming.

"There's a lot of option football here," Kelly said. "It's not probably somewhere you want to blitz. You have to play assignments."

Purdue had a different style of offense but did go to the zone read in the second half. That resulted in the Boilermakers' only touchdown, as Robert Marve ran 23 yards for the score. Purdue also had some success earlier in Wildcat formations. A red flag?

Kelly said it was more a matter of being caught a little off guard, and that once defensive coordinator Bob Diaco changed some calls, the Irish were ready for that look. Also notable: that Marve touchdown was the longest play allowed by the Irish defense, which for the most part kept things contained very well.

"Our goal is to minimize the big play," Kelly said. "That's clearly the message. Some times if you bring a lot of pressure, you put yourself in position to make plays or to give up plays. We have to pick our spots."

Kelly's 2009 Cincinnati team ranked last nationally in time of possession with its quick-strike offense, and on Saturday Notre Dame had the ball for only 24:55, which puts the Irish 96th in the FBS in that category after one week. But Kelly said that won't be the case every week, and that he wants the defense on the field a lot less.

"At Cincinnati, we made the decision to shoot more threes than we give up," he said. "I don't like to play that way but that's the way we needed to play.

"I'd like to manage the game in a more textbook fashion, if you will. Our style of play brings [controlling the time of possession] into the thought process. Last year, I couldn't even think about it. It was just, score as fast as you can."

Keeping Robinson off the field as much as possible is probably a good idea. Kelly said it's difficult to prepare for such an athletic quarterback and the speed at which he plays. He wouldn't say who would impersonate Robinson on the scout team this week but said he had a few options.

Don't expect big changes from the defense. What you saw in Week One -- sound principles, containing the big play -- wasn't just an opening argument. It's the case Notre Dame expects to make every week.

"We're not going to be that different with our scheme," Kelly said. "We are who we're going to be."