On Sunday in London, Allen brought down one of the toughest quarterbacks in the NFL, Ben Roethlisberger, and he did it three times, getting credited with a half sack on one of those.
After managing only one sack in the first three games of the season, Allen came up with 2½ sacks – all in one drive – in the second quarter of the Vikings' 34-27 win over Pittsburgh.
It was an emphasis for the Vikings entering the game.
"We need to play better up front. It's hard for our team to be successful if our offensive line and our defensive line are not playing at a high level," head coach Leslie Frazier said last week. "Our guys know that, our team knows that and we've got to help them to get to that point."
After the Vikings had just scored a touchdown on a 60-yard Adrian Peterson run on their first play from scrimmage in that series, Allen and his defensive teammates were back on the field in less than 20 seconds of game time. On second down, Allen sacked Roethlisberger for a 1-yard loss. The Steelers converted third-and-11 on the next play.
Five plays later, Allen and rookie Sharrif Floyd combined for a sack of Roethlisberger on second down. The Steelers converted third-and-12 with a 28-yard pass to tight end Heath Miller that had 15 yards added onto the end of the play because of a helmet-to-helmet hit by Harrison Smith.
The Steelers were inside the 20-yard line and looking to score after that conversion, but six plays later Allen brought down Roethlisberger for a 5-yard sack on third down that forced Pittsburgh to settle for a field goal and trail by seven points.
"We kind of say when rush and coverage matches up, that's when we make plays. The rush was there all night long," Smith said. "We've still got to shore some things up on the back end, but ultimately it was enough to win."
Roethlisberger entered the game having already taken 10 sacks over the previous three games behind a shaky offensive line that is without center Maurkice Pouncey, who is on injured reserve. Last week, Roethlisberger said it was a combination of things leading to the pressure, but he also shared some of the blame.
The Vikings pounded on the opportunity to get to Roethlisberger, and he proved elusive enough early in the game. Erin Henderson, Brian Robison and Allen had all failed to bring Roethlisberger down when they had their hands on him in the first two series of the game.
Allen didn't let many more opportunities slip away the rest of the game and the Vikings finished with five sacks, including the game-sealing one by Everson Griffen that caused Roethlisberger to fumble away his last opportunity.
In the first three games, the Vikings had four sacks combined. In their fourth game, they had five, and Allen was a big reason for that.
BUCKING THE TREND
Matt Cassel had quite the outing in his first start as a Viking. He completed 16 of 25 passes for 248 yards, two touchdowns, no interceptions and a 123.4 rating. The rating was higher than anything Christian Ponder had produced in his 29 starts as a Viking.
Although head coach Leslie Frazier was non-committal on who would start after the bye week, he had to admit that Cassel's performance gave the coaching staff something to think about during the bye, despite what Frazier said prior to the game.
"I'm hoping that he shines, but I don't foresee a quarterback controversy," Frazier said on Friday. "We want him to play lights-out and have the best game of his NFL career."
It wasn't the highest rating of Cassel's career but it bucked the trend he had created when he previously played the Steelers.
Cassel had started 62 games over a five-year period with the New England Patriots and Kansas City Chiefs, but in three previous games against the Steelers, Cassel has completed only 47 percent of his passes for 571 yards, two touchdowns and three interceptions.
Smith said two weeks ago that he had $40,000 in fines last year for illegal hits on receivers. He may get a letter from the NFL fine doctor again this week after being flagged for hitting Miller in the helmet after during a 28-yard reception.
"Ultimately, Heath Miller, he had a knee injury last year, right? As a player, as a fan, I know that. I don't want to hit him in the knee," Smith said. "I tried to keep my head out of it. I didn't launch. I don't really know what else to do. There was a play later where I hit him lower and I didn't want to do it, but I had to. That might have made him mad. Ultimately, we're trying to win the game. It's tough. I really don't know what else to do in that situation."
Smith said he thought Miller lowered his head, but said the NFL has told him that even if that happens and the defender makes contact with the helmet, it will result in a fine.
"That's pretty unreasonable," Smith said.
RAYMOND, HODGES DEBUTS
With safety Jamarca Sanford out with a hamstring injury, Mistral Raymond made his 2013 debut. Andrew Sendejo got the start in place of Sanford, but he and Raymond essentially split snaps. Sendejo played 42 of the 79 snaps and Raymond played 36.
Raymond and Sendejo each had four tackles.
Rookie linebacker Gerald Hodges was active for the first time in his career and played seven special teams snaps. He had one tackle on kickoff coverage.
Tim Yotter is the publisher of Viking Update. Follow Viking Update on Twitter and discuss this story on our subscriber message board.