They come in different shapes, sizes and signature moves, but there is one common trait that all great NFL pass rushers have.
"They're relentless, like the big-game hunter born to stalk his prey," said former Vikings defensive end Jim Marshall, whose 127 career sacks rank second in team history.
"They have the inner 'want-to' on every single play of their careers," said Chris Doleman, another former Vikings defensive end, who holds the team season record of 21 in 1989.
"It's like this," said John Randle, a Vikings Hall of Fame defensive tackle with 137 1/2 sacks. "A great pass rusher looks at 1,000 doors. He's been told there is a sack behind just one of those doors. It might be the first door. It might be the last door. The great pass rusher opens every single door just as hard as he did the first door."
In keeping with the pass-rushing tradition built on the wide shoulders of such men as Marshall, Carl Eller, Alan Page, Keith Millard, Doleman and Randle, the Vikings have two defensive ends -- Jared Allen and Brian Robison -- who are opening doors relentlessly this season. Allen already has established himself as a great NFL pass rusher at right end. Robison is a rising star who's quickly making a name for himself in his first season as a starter at left end.
Together, they have 13 sacks, the most by two teammates and, believe it or not, more than 22 entire NFL teams. Allen leads the league with 8 1/2, while Robison has matched his career high (4 1/2) in just five games. And, as their good fortune would have it, they now head to Soldier Field on Sunday night to face Bears quarterback Jay Cutler, who has been sacked a league-high 70 times and beaten mercilessly in his past 20 regular-season games.
"Jared is a great one," Randle said. "Jared keeps going even if it takes up to that 1,561st door and then, bam! It's a sack. That's why you see him down on the ground doing that lasso celebration of his. No better feeling."
As for Robison, consider his Purple forefathers impressed.
"I like the guy," Randle said. "If you look at the footsteps he's following -- Eller, Page, Doleman, Jared -- he's like a new singer going on stage after Prince or Elvis. But I think he's definitely risen to the occasion so far."
Night and day
Allen and Robison often meet at the quarterback. What they do to get there is totally different, however.
"Jared's taller and has longer arms, so some of the things he does with his hands, I wouldn't do," said Robison, who, at 6-3, is 3 inches shorter than Allen.
"I'm a technique-leverage guy, whereas Brian is a speed guy off the edge," said Allen, who's listed at 270 pounds but says he actually plays at 255. "Brian can beat you with speed and a spin, like a Dwight Freeney. You won't see me doing any spins."
Allen leads the NFL with 91 1/2 sacks since joining the league in 2004. His 48 1/2 sacks since coming to the Vikings in 2008 are the most by a Viking after four seasons. And he's got 11 games left to add to that total, which already leads Eller by 9 1/2.
"A great pass rusher is always moving his feet, and that's Jared," Randle said. "And each guy has what I call his bread-and-butter move. Jared's is using his hand to post a guy, and the split second the guy sets his feet, Jared can use his other hand to pull the guy's arm and swim by because Jared's feet are always moving. The difference between making a play and not making a play is taking advantage of that one second when that blocker sets his feet."
Allen's reliance on hand techniques is one reason he incorporates so much mixed martial arts training into his offseason routine.
"John Randle had a great hump move, but I'm not a guy who is going to hit you with my left arm and send you rolling down the field," Allen said. "So I'm big into hands. I know if I can stop your hands, I can stop your feet. And as a pass rusher, once you get a guy to stop his feet and punch his hands, you can break him down."
Robison has only 18 career sacks but was a role player behind Ray Edwards for his first four seasons. When both were free agents after last season, the Vikings signed Robison and let Edwards walk. He signed with Atlanta and has one sack this season.
Allen and Robison have become friends as well as friendly rivals. Allen, 29, is only a year older, but he's the mentor. And although their styles differ, Allen can share some of the knowledge he's gained going back to his first NFL defensive line coach, the late Bob Karmelowicz.
"When I first got to Kansas City, Bob told me, 'If you get a sack one out of every 19 rushes, you end up with 17 1/2 sacks for the year,'" Allen said. "That's a great year, 17 1/2 sacks. But, like Bob said, how do you handle those 18 other rushes that were failures? Using those 18 rushes to set up the move that ends up being a sack is key."
Vikings coach Leslie Frazier was a cornerback for the Bears, but he learned a lot about great pass rushers as a teammate of Hall of Famer Richard Dent.
"They all have the football instincts and intelligence that you wouldn't necessarily associate with a defensive end," Frazier said. "I can remember Richard telling me at times, 'Hey, I'm going to use this move ... watch this guy because he's going to take this fake and I'm going to be on the quarterback.' Same thing with Jared. He'll say, 'I'm going to do this and this is going to happen.'"
Comparing pass rushers from the days the Vikings joined the league in 1961 to today is fun but "impossible," said Marshall, who played with the Vikings from 1961 to 1979.
"Guys like Jared and all the great pass rushers of today have so many more restrictions on what they can do," Marshall said. "That's one reason I admire Jared as much as I do. He's able to do what he does while walking that fine line between aggression and all the rules and fines that are designed to protect the quarterback.
"Back in the Purple People Eater days, the fines we would have faced playing the way we did, our entire salaries would have been spent in fines by midseason."
Allen and Robison both make it a point to know their Purple pass-rushing lineage.
"First of all, those Purple People Eaters weren't just pass rushers, and I don't consider myself just a pass rusher either," Allen said. "You watch the film of those guys back then. They were some violent SOBs in the trenches. Those are the guys I try to model myself after."
Allen is on a pace for 27 sacks, which would be 4 1/2 more than the NFL record of 22 1/2 set by Michael Strahan in 2004. But Allen knows sacks are fickle enough that their projected pace at any given time means nothing.
For now, he and Robison will continue trying to see which one can get to the quarterback first.
"My competition is really with myself," Allen said. "But I ain't letting no first-time starter beat me, if you know what I'm saying."
Robison laughs. He's also ultracompetitive by nature.
"If you want to be the best, you got to beat the best," Robison said. "As [Randle] said, you got to keep on pushing. Right up to that 1,000th door, if that's what it takes to get that sack."