LONDON – Matt Cassel paced the sideline, hands on his hips. His teammates stared at the scoreboard clock, hoping those final seconds would just tick, tick, tick away.

They had seen this horror show before. Twice already, actually. Back-to-back final minute collapses seared their memory as they tried to prevent a heartbreak trifecta on Sunday evening 4,000 miles from home.

"You get in that situation again and you think, 'Ah, here it goes again,' " left guard Charlie Johnson said.

On the field, the Vikings defensive line looked at each other in the huddle and shared a singular edict: Somebody has to make a play.

Turns out, they all just decided to meet at the quarterback. A wave of rushers enclosed Pittsburgh quarterback Ben Roethlisberger with less than 10 seconds left and the Steelers practically within spitting distance of the goal line and overtime.

Everson Griffen hauled him down from behind and knocked the ball free, Kevin Williams pounced it and the Vikings' European experience ended with a giant exhale after they secured a 34-27 victory before a festive announced crowd of 83,518 at Wembley Stadium.

"Man, we needed that bad," defensive end Brian Robison said. "I'd hate to lose this game and have a seven-hour plane ride back."

It's perhaps overly dramatic to label Week 4 a must-win, but anything less than that would have sent the Vikings season on an undesirable path. Their first victory will be memorable on many levels, first and foremost because a "home" game took place on foreign soil.

The Vikings spent much of the week in seclusion outside London, attempting to rid themselves of frustration after two consecutive late-game collapses. And within that cocoon they learned that Cassel would take over at quarterback for Christian Ponder, sidelined by a fractured rib.

So when Leslie Frazier's defense made one final play to thwart Pittsburgh's rally and keep the Steelers winless at 0-4, a palpable sense of relief flowed inside the locker room.

"We've had some tough losses," Frazier said. "In the fourth quarter of every one of these ballgames we were right there. So to come away with a win in the fashion that we did, this many miles away from home, knowing what it takes to keep a team together after some of those tough losses …"

The focus, of course, shifts to the quarterback situation and how Frazier plans to proceed once the team returns from its bye.

Cassel gave the offense an unmistakable spark and looked aggressive in throwing the ball downfield, an area sorely lacking with Ponder at the helm. Cassel completed 16 of 25 passes for 248 yards and two touchdowns for a 123.4 passer rating.

Frazier was noncommittal about his quarterback plans for the Carolina game in two weeks. Ponder was asked if he still believes he's the starter.

"That's what I expect [but] that's out of my control right now," he said. "For us, we're just going to enjoy this win. I'm so proud of Matt and the way he played the whole team played. He couldn't have played better."

The offense hummed efficiently behind big plays in the passing game and 140 rushing yards and two touchdowns by Adrian Peterson. Greg Jennings caught two touchdown passes, including a 70-yarder, and Jerome Simpson continued his fast start with 124 yards on 11 catches.

"Matt played phenomenal," Jennings said. "He's a true professional. Matt doesn't carry himself as a backup. He carries himself as starter. He prepares as a starter. He got an opportunity and he came up big."

Cassel's 16-yard touchdown pass to Jennings late in the third quarter gave the Vikings a 34-17 lead and they looked firmly in control. But the positive vibe quickly melted as Roethlisberger kept firing passes against a depleted Vikings secondary. Big Ben attempted 51 passes and finished with 383 yards.

A rare miss on a field-goal attempt by Blair Walsh from 44 yards and a subsequent Steelers field goal cut the Vikings lead to 34-27.

Gulp.

"It was definitely a nail-biter," Simpson said.

Vikings players — and their fans — probably got down to their nubs as Roethlisberger quickly moved the offense to Vikings 6 with 24 seconds left. A spike and an incomplete pass set up third down.

Considering what happened against Chicago and Cleveland, another blown lead might have sent their season into an abyss.

"We didn't have the mentality that it's going to happen again," Vikings linebacker Chad Greenway said.
This time they finished the job. The Vikings still face an uphill climb at 1-3, but their long flight home Monday morning will feel much different from it did coming over.

"When you get that win, it's a whole different feeling," safety Harrison Smith said. "Your body doesn't hurt so bad. Everybody is happy. You get confidence. That can really build."
Chip Scoggins • chip.scoggins@startribune.com