"What we did in the first half was we kind of stayed back and we kind of played coverage," Rivera said. "We felt if we got physical at the line of scrimmage with the receivers, maybe we could kind of contain them. But they (the Vikings) handled that with success.
"They hit the big pass on us, which was kind of disappointing."
The cover-two zone look and a four-man or three-man pass rush had given up 166 yards on 11-of-15 passes and touchdowns of 5 yards to Nate Burleson and 40 yards to former Bear Marcus Robinson. The Vikings didn't even have to punt in five first-half possessions.
"We came back in and we talked about it as a staff and I really felt we could bring pressure -- and it was a great suggestion by the other assistant coaches as well. And we decided to cut loose and the players really responded," Rivera said.
The Bears had their second-best sack day of the year with five sacks, four in the second half, after increasing the pressure on Culpepper. Brian Urlacher had a key fourth-quarter sack on a blitz. Adewale Ogunleye and Alex Brown made sacks and Alfonso Boone had a career-best two sacks.
They had their hand on Culpepper enough to force him into several errant throws and a few wild looking panic completions. Six times in the second half Culpepper needed more than 10 yards for a first down.
The better pressure made the Bears better on third down in the second half, as well. Leading the league in defending third down, the Bears had given up 4-of-4 third down conversions the first half. In the second half they were 3-of-6.
"We've got to get after the quarterback," Brown said. "That's what makes our defense play well. A lot of pressure gets put on us up front. We want it. We feel like we can handle it.
"If we get up the field, he's got to go somewhere. He can't sit back there like in the first half."
Brown said he thought the pass rush could gamble more without worrying about Culpepper's great speed on scrambles because Urlacher was back from calf surgery after two games away.
"We've got 54 in there, if we don't get him, he (Urlacher) runs and runs and he'll run (Culpepper) down," Brown said.
Culpepper, who had 50 yards on six scrambles, even had to acknowledge the Bears' pressure up front after the game.
"I commend those guys for having a great game plan of putting tons of pressure on me," Culpepper said. "I have to give them credit. They did a great job. It's just too bad we have to wait a whole year to play them again."