Both Donald Driver and Al Harris expect to see something from the Chicago Bears' defense on Sunday that isn't necessarily their forte - blitzing.

In separate interviews with Sirius NFL radio this week from Miami, site of Super Bowl XLI between the Bears and Indianapolis Colts, Driver and Harris indicated the key for Chicago against the Colts' high-powered offense will be to pressure quarterback Peyton Manning any way they can.

"The Bears' defense is great, but the only thing is they have to put pressure on Peyton Manning," Driver said. "If they don't put pressure on Peyton Manning, he's going to be able to sit back in the pocket and pick that secondary apart."

But Driver doesn't think the Bears can simply rely on their front four, which they normally do in their Cover-2 scheme, to get to Manning. Assuming middle linebacker Brian Urlacher stays in his customary deep middle spot, the blitzing could come from the outside linebackers.

"They want to rush four and they hope their four guys get to the quarterback, but I don't see that happening," Driver said. "I think they'll have to blitz with Lance (Briggs) and (Hunter) Hillenmeyer."

Harris said the Bears are certainly capable of doing that with Ron Rivera as their defensive coordinator. Rivera was the linebackers coach at Philadelphia under coordinator Jim Johnson, renowned for his blitz packages, when Harris played for the Eagles.

"Ron is going at them," Harris said. "He's an understudy of Jim. Ron is going at them."

But a big missing link in that Bears' defense against a passer like Manning is safety Mike Brown, who was lost to a season-ending injury in October. Driver likened it to the Patriots missing safety Rodney Harrison in their AFC Championship loss to Indianapolis two weeks ago, when the Colts scored 32 second-half points. That will put added pressure on Chicago safeties Chris Harris and rookie Danieal Manning to prevent any deep throws.

"Mike Brown is like a Rodney Harrison, he's the heart and soul of the secondary, and a lot of times if you don't have them back there, it doesn't work out," Driver said. "I think Harris and Manning both have to come together and realize they have to be the ones to set that secondary up."

Similarly, the key to the Colts' secondary will be safety Bob Sanders against what Driver and Harris consider a somewhat underrated Bears offense. Sanders' return from injury has bolstered Indy's run defense, and if the Bears can use their physical style and stable of running backs (Thomas Jones, Cedric Benson and Adrian Peterson) to force Sanders to play closer to the line of scrimmage, it could open things up in the passing game for Rex Grossman.

"That will play a big part," Harris said. "Somebody is going to be one-on-one with (Bernard) Berrian or Moose (Muhsin Muhammad). Moose can hurt you if you underestimate him."

Driver agreed.

"Their receivers are good. Those guys can make plays," he said. "Grossman has to be confident in himself that he can make the plays. He can't let the hype get to him. He has to go out and play his style of football. No one is giving them the credit. They have to go out and play."

Both Packers were leaning toward predicting a Colts' victory, but both were giving the Bears a legitimate chance to pull the upset.

"A lot of plays out there are going to be given to you," Driver said. "You have to make those plays count."