Drew Brees proved that he's human Sunday night. He threw an interception.

He also got to sit in the passenger seat for a change.

The NFL's all-time leading passer had an unusually quiet performance, but the New Orleans Saints showed they can win using a different formula than run-and-gun offense.

Their defense did the heavy lifting — or taking away, in this case — for a 30-20 victory over the Vikings at U.S. Bank Stadium.

How atypical was their script? New Orleans led 27-13 entering the fourth quarter and Brees had only 102 yards passing.

The fact that the Saints won their sixth consecutive game in a rout on the road despite a pedestrian outing from Brees provides further evidence that they are legitimate contenders.

The Vikings deserve an assist for shooting themselves in the foot.

"You're ready to take advantage of whatever opportunities the opposing team gives you," Brees said.

Oh, the Vikings gave them opportunities all right. Two big ones.

The Saints defense looked like easy pickings early but flipped the game upside down by forcing two turnovers that saved points and scored points.

The Saints pass defense ranks among the NFL's worst, and Kirk Cousins repeatedly targeted cornerback P.J. Williams from the opening series.

Williams gave up several long completions in coverage while also committing a pass interference penalty in the end zone. He went from being picked on to hero with two plays.

The Vikings led 13-10 late in the first half and were driving for more points. They had a chance to go ahead by two scores, and also get the ball to start the second half.

But Williams joined linebacker Alex Anzalone on a tackle of Adam Thielen that knocked the ball loose at the Saints 14-yard line. Cornerback Marshon Lattimore scooped up the fumble and returned it 54 yards to the Vikings 33.

The Saints turned that takeaway into a touchdown for a 17-13 halftime lead.

"It was definitely a turnaround," Williams said. "We started off slow. I was giving up a few plays. A turnover always turns the game around. It definitely swung the game."

His takeaway in the third quarter essentially put the game out of reach.

Stefon Diggs ran a crossing route but stopped running as Cousins started to throw. Diggs stopped running, Williams didn't — and Cousins' pass landed in his arms.

Williams returned that gift 45 yards for a touchdown and 27-13 lead.

"I'm sure [Cousins] didn't see me," Williams said. "He saw Diggs coming across the field, and I'm sure he thought he was going to keep going."

Williams credited his ability to overcome a disastrous start to "mental toughness."

"You're going to get beat in this league," he said. "You just have to stay in it."

Their turnovers meant the Saints didn't need a typical Brees performance, though watching him overthrow his intended target for an interception was like seeing a UFO streaking across the sky. You rub your eyes and say, "Wait, what was that?"

On the play, Stephen Weatherly applied pressure off the edge after being unblocked, forcing Brees to rush his throw to Michael Thomas over the middle. His pass sailed high and Harrison Smith leaped to grab it.

That ended Brees' streak of passes without an interception at 231 to start season.

"Shouldn't have happened," Brees said. "I had a little bit of pressure, but I should just keep the ball down."

Brees finished with 120 yards passing and one touchdown. His longest completion was 20 yards. The Vikings outgained the Saints 423 yards to 270.

"Offensively, we were efficient," Brees said. "There weren't a ton of big plays."

The Vikings never recovered from Thielen's turnover. That momentum swing sucked the air out of the team and the stadium. The second half had a weird vibe to it.

"We just know how to win," Williams said.

Usually, that entails jumping on Brees' back. Not this time. The defense took the starring role after a shaky start.

"This one had a little extra special meaning," Brees said. "Obviously the difference was getting some of those turnovers."

Chip Scoggins • chip.scoggins@startribune.com