Peterson's brilliance not helping Vikes' air game

When Adrian Peterson lay prone on the Washington turf last December with a shredded left knee, even his most ardent supporters would have had trouble believing he would reclaim his standing as the NFL's best running back just 10 months later.

His remarkable return to prominence has been one of the feel-good stories of the season. It's also shaking the very foundation of the Minnesota Vikings' offensive philosophy, and one of the longest-held tenets in football: that success on the ground will open things up in the passing game.

Peterson is getting better and better every time he steps on the field this season, more closely resembling the powerful cutback runner he was before tearing two ligaments against the Redskins late last season. It's been an incredible recovery, punctuated by three straight 100-yard games, including a breath-taking 144 in the first half alone last week against Seattle.

He finished with 182 yards and two touchdowns against the Seahawks, following up a 123-yard effort against Tampa Bay and 153 against the Arizona Cardinals. He leads the NFL with 957 yards rushing and 1,107 yards from scrimmage, accounting for nearly 37 percent of the Vikings' total offense.

For decades, the belief in the NFL has been that a successful run game will set up big gains down the field by getting safeties to creep up closer to the line of scrimmage and create one-on-one matchups outside. Even in this day and age of pass-happy offenses, the Vikings have stayed committed to that approach.

While Peterson has run better and better each week, the pass offense has been stuck in a downward spiral over the last three weeks. Christian Ponder threw for 58 yards against Arizona, was able to pad his stats in garbage time against Tampa Bay, then managed just 63 yards in the loss at Seattle.

''Usually when you run the ball as well as we're running it, you get some easier route combinations that you can have success with because of the eight- and nine-man fronts that we're getting,'' coach Leslie Frazier said Thursday. ''But it hasn't materialized for us. We're trying to figure that out and trying to capitalize on how well we're running the ball, which creates a lot of single-safety situations for our offense to see.''

The problems are many. Receivers are having difficulty creating separation, Ponder has been woefully inaccurate with his throws and the Vikings (5-4) have struggled at times to pick up the blitz and keep their quarterback protected while losing three of their last four games.

Put quite simply, opposing defenses are not viewing the Vikings' downfield passing game as a threat. That means they're not biting on play-action fakes as hard as they did early in the season, not having to commit a safety to double-teaming any of their receivers and therefore are able to turn loose extra pass rushers to put as much heat as possible on Ponder, who has looked skittish in the pocket.

''It just comes down to needing to execute and be more balanced on offense,'' center John Sullivan said. ''Obviously we're committed to running the football. We're going to do that in every game we play. Theoretically it should open up the passing game. That hasn't been happening. Our focus this week is trying to get the pass game going while continuing to do what we've been doing in the run game.''

Peterson vowed to be ready for Week 1 of the season, but there were plenty of skeptics. He scored two touchdowns and rushed for 84 yards in the opener against Jacksonville, but it was apparent he was missing just a little bit of that top gear that made him so special before the injury.

He grinded out some games against Indianapolis and San Francisco before topping 100 yards for the first time at Detroit, but was still looking for the big breakaway runs that were a hallmark of his first five years in the league. They've started to come in the last two games. He scored on a 64-yard run against the Bucs, then ripped off a 74-yarder while averaging 10.7 yards per carry against the Seahawks.

''It's a little frustrating,'' Peterson said after the game. ''You just see what you can do and see how you can improve and go from there. That's going to be our focus point; establish the run and try to be more productive in the pass game. It's obvious we didn't have a big game passing. But we'll work on it.''

Offensive coordinator Bill Musgrave said he is re-examining the routes his receivers are running, the protections being assigned to the offensive line and running backs and everything else to try to get the passing offense going.

''We're not at all pleased with our production. We need to get back on track,'' Musgrave said. ''Everybody can sense that. We're very disappointed. Not at all discouraged, but very driven and determined to get it back on track.''

It could be made more difficult this week against the Lions if star receiver Percy Harvin is unable to play because of a sprained left ankle. He was still hobbling around Thursday and appeared to be a long shot to practice Friday. Peterson missed practice as well with an illness, but is expected to play against the Lions.

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