Matchup to watch: Which defensive end?

The Vikings have some questions at defensive end with the unclear status of Jared Allen. Whether Allen can play or the Vikings turn to second-year DE Brian Robison, whoever starts will face a difficult challenge from Green Bay left tackle Chad Clifton.

With questions swirling around the availability of Jared Allen for today’s critical matchup with the Green Bay Packers, how the Vikings plan to attack the left side of the Packers offensive line makes the battle between left tackle Chad Clifton and either Allen or second-year end Brian Robison this week’s matchup to watch.

Even if he was 100 percent, there would be no guarantee of success for Allen against Clifton, acknowledged as one of the best left tackles in the game in his ninth season. Allen has played Clifton twice in the last year – in Week 1 in his Vikings debut and last November while a member of the Chiefs. In both games, Clifton frustrated him and effectively neutralized his pass rush on almost every play. And that was Allen at 100 percent, which it is clear he is not at this point.

The full extent of Allen’s health or lack thereof is up to debate. In his first interviews since the injury, when asked the severity of the injury to the AC joint in his right shoulder, Allen said he thought he was told it was a Grade-3 (the worst of the three possible strains and tantamount to a separated shoulder that typically sidelines a player two to four weeks). However, Allen appeared to have good range of motion during the week and had no harness or wrapping on the shoulder when he met with the media several times.

Could the Vikings be playing mind games with the Packers and the fans in hopes of getting a roof-blowing reaction when Allen is introduced in the starting lineup? Or is the injury as serious as many are speculating? We likely won’t find that out until shortly before game time. If Allen isn’t deactivated, he will likely be in the starting lineup. If he is inactive, Robison will have to step in.

Used primarily as third-down pass rusher as a rookie last year, Robison moved into the starting lineup late in the season due to injuries and a suspension to Ray Edwards. He proved he could hold up playing almost every down rather than simply being a situational pass rusher. Despite the addition of Allen, Robison has seen more snaps on average this year than he did during the first two months of his rookie season. If Allen can’t go, Robison will have to test his speed-rushing techniques against one of the more polished offensive tackles in the game.

Clifton is in his ninth season and, as one would expect, age is starting to diminish his skills. He has chronic knee problems that limit his use in practice during the week, but he’s a consummate pro on game day. He hasn’t missed a game since 2002, when he was nearly beheaded by a cheap shot from Warren Sapp following an interception. He has been durable and plays with extremely good technique play in, play out.

What makes this matchup so critical is that the Vikings need to pressure quarterback Aaron Rodgers. A dangerous runner when given a chance to escape the pocket, Rodgers is capable of making big plays when he takes off and runs. He is also very accurate when given time to deliver the ball without pressure. He was able to find a comfort zone in the first meeting this year and led the Packers to their fifth straight win over the Vikings. Making his first start in the Metrodome, Rodgers has yet to deal with the kind of crowd noise he will face when Vikings fans are in full throat. It makes calling audibles extremely difficult and the shotgun formation becomes a problem in that the exterior linemen, like Clifton, will have to look to the ball to see it move rather than being able to anticipate the standard snap count, making them a half-step slower off the snap. With speed rushers like Allen and Robison, that could make the difference between Clifton steering them out of the play and being beaten off the snap and opening up Rodgers to a potential blindside sack.

The Vikings have benefited greatly from the addition of Allen, who, through eight games, already has more sacks that any Viking defender had during the entire 2007 season. His value to the team has been instant and impressive, giving the team a pass-rush presence that has required offenses to change what they do with their fullbacks and tight ends in response to Allen’s ability to make game-changing plays. If he is out, Robison will have to shoulder the load that Allen’s shoulder won’t permit him to do. Either way, Allen and/or Robison are going to have a huge challenge in trying to overpower and out-quick Clifton – making this the matchup to watch today.