GLENDALE, ARIZ. – Hours before kickoff of the Vikings' 34-33 loss to the Cardinals on Sunday, cornerback Patrick Peterson walked a lap around the field at State Farm Stadium where he made many of his 154 career starts and 28 interceptions for Arizona over 10 seasons.

But on this lap, Peterson didn't stop to gladhand with any former teammates or coaches. He paced past the Cardinals sideline wearing headphones that shut out noise. It was a business trip. That's what Peterson told himself leading up to his return to Arizona, where he felt disrespected with how Cardinals General Manager Steve Keim let him walk in free agency last offseason.

And Peterson nearly had the last laugh, if not for one too many big plays by Cardinals quarterback Kyler Murray.

"It felt like a regular game," Peterson said after leaving the visitor's locker room. "That's how I wanted to approach it and keep myself grounded and relaxed throughout the game, as well, and not let my emotions get too high."

"I just wish I would have had one play back," he added.

Peterson, a three-time All-Pro selection with the Cardinals, played well considering his primary assignment, receiver DeAndre Hopkins, was targeted on just four of Murray's 36 throws. But Hopkins caught all four throws, including a 15-yard touchdown in which Peterson lost him on a scramble drill. Murray evaded pressure and scrambled left, so Hopkins rerouted to the same side, leaving Peterson in the dust.

Peterson said he has to "keep my eyes on the receiver," but otherwise head coach Mike Zimmer approved of Peterson's play despite Murray throwing for 400 yards and three touchdowns.

"He did really well," Zimmer said. "I don't remember many catches on him [Sunday], the same as last week. He's a good pro. We didn't help him all that much [in coverage]. He played well. I'm glad we have him."

Big plays still busted the Vikings.

Zimmer's defense allowed five "explosive" throws, classified as 20-yard gains or longer. Some stemmed from botched coverages; others simply left Vikings defenders shrugging. There was little that could've been done differently, Zimmer said, when Murray backed up and lobbed a 35-yard pass to receiver Christian Kirk on fourth down in the fourth quarter.

Zimmer called a blitz. Safety Harrison Smith got there, and was in Murray's face when he completed the moonshot to Kirk that led to a 27-yard field goal, giving the Cardinals a 34-33 lead with 4:26 left.

"[Murray] did that last week against Tennessee, too," Zimmer said. "It was one of those deals where you're trying to create something to happen. You're hoping for a short throw, and he just drifted back."

Murray later attacked cornerback Bashaud Breeland, who was in and out of the game because of back tightness, with a 29-yard deep ball to receiver A.J. Green on a go route.

Arizona also struck just before halftime, like the Bengals did with a 50-yard TD in Week 1. This time, rookie Rondale Moore was wide open for a 77-yard catch and run. Someone messed up their coverage assignment, Zimmer said; safety Xavier Woods was the closest defender to the receiver.

According to Peterson, teams that score before halftime have a "76 percent chance of winning."

So far, Vikings opponents are 2-for-2 on that front.

"That was a tough bullet to bite right before halftime," Peterson said.