Bill Belichick will compare gray matter with Mike Zimmer and Norv Turner on Sunday.

We haven't seen a clash of neurons this intriguing in decades.

Maybe you have to go back to the late '80s and early '90s, when Tom Kelly and Tony La Russa would turn games between the Twins and A's into treatises on intricate baseball strategy, both making moves in the sixth inning while eyeing the guy at the end of the bench who could win the game in the ninth.

Maybe you only have to go back to the mid-'90s, when Tony Dungy's defenses tried to stop Mike Holmgren and Brett Favre.

In the Vikings' Week 1 victory at St. Louis, Zimmer and Turner produced the first Vikings victory directly attributable to coaching in a long time.

Turner, the Vikings offensive coordinator, minimized the effectiveness of the Rams' strong front seven, and used unusual, inside play fakes to Adrian Peterson in the red zone to create openings for Matt Cassel's two touchdown passes.

Minnesota Vikings head coach Mike Zimmer.

Zimmer, the Vikings head coach and de facto defensive coordinator, confused the Rams' offensive line, helping his defensive front stuff the run and pressure the quarterback.

The result was a 34-6 victory over a team favored by Las Vegas.

This week, Zimmer and Turner will face an increase in degree of difficulty, like progressing from checkers to quantum physics. They will be challenged not only by Belichick's expertise, but a matchup that should prove far more confounding than facing a couple of backup quarterbacks and a rudimentary offensive scheme.

The last time the Patriots came to town to face a popular rookie head coach in Minnesota, Belichick embarrassed Brad Childress.

The Vikings were 4-2. Minnesotans viewed Childress as a savior. The Patriots were 5-1.

The Vikings had proved to have a strong run defense, so the Patriots used four- and five-receiver formations. Tom Brady threw 43 passes. The Patriots attempted 15 runs. The Patriots won 31-7.

Exposed as limited and predictable, the Vikings would win only two of their last nine games.

The Vikings victory at St. Louis set up a similar sequence in terms of defensive challenges. In St. Louis, the Vikings won by beating a team determined to run the ball. Sunday, they face a team willing to use extra receivers to expose inexperienced defensive backs.

If the Vikings fare better against the Patriots, it will probably be because of Zimmer.

He and Belichick both made their reputations in the NFL as longtime defensive coordinators who worked under Bill Parcells, yet Zimmer says he can't remember ever having a conversation with Belichick.

The last time they faced each other, last year in Cincinnati, Zimmer's defense held the Patriots to six points and forced Brady to complete a season-worst 47.4 percent of his passes. It was the only game in which the Patriots scored fewer than 13 points. "I wouldn't be surprised if they Xeroxed the game plan," Belichick said.

Zimmer tried to defuse the notion that he could have an advantage on Belichick. "I know he's going for 200 victories and I'm going for No. 2," Zimmer said Friday.

But this will be the first time a Vikings team has faced Belichick's Patriots with a chance to make the league's foremost genius uncomfortable.

Last week, Zimmer protégé Kevin Coyle helped the Dolphins beat New England, 33-20. This week, Belichick expects Zimmer to attempt to pressure Brady from all angles.

"Strong side, weak side, up the middle, secondary pressure, linebacker pressure," Belichick said. "Yeah, they do a good job keeping you off balance. I'd say that's one of their real strengths is they give you a bunch of, not so much different looks but different combinations off similar looks. You have to be ready for everybody. You can just say, 'It's going to be this or it's going to be that.'

"Sometimes it's strong side, sometimes it's weak side, sometimes it's up the middle, sometimes it's man, sometimes it's zone, sometimes it's blitz zone, sometimes it's all-out blitz, sometimes it's just max coverage and they drop everybody off, but off that same look."

For once, Belichick will face a Vikings team that won't worry that it's being outcoached while the opening coin flip is still airborne.