Under particular scrutiny is the defense, where assistant coaches, players and even the scheme itself are being examined by coach Leslie Frazier and general manager Rick Spielman this week.
Defensive coordinator Fred Pagac's status is up in the air. Injuries depleted the secondary, and it wasn't that deep to begin with. Outside linebacker Chad Greenway's production dropped off. The nose tackle spot vacated by Pat Williams was never solidified. Top-tier quarterbacks like Aaron Rodgers and Drew Brees simply picked this group apart.
The Vikings have used a version of the Tampa Two zone coverage system with a 4-3 alignment for years, so naturally the questions have arisen about whether it's time for them to switch to the trendier 3-4 scheme that several playoff teams have used successfully.
But Frazier, whose background has been solely in the 4-3 system, expressed caution.
"You don't want to jump on the bandwagon purely because it's popular in some other city, and they've had success. If it doesn't fit what you do, you better do what fits you," Frazier said.
Despite all their defensive troubles, the Vikings tied for the NFL lead with 50 sacks, and Jared Allen finished with 22, one-half short of the all-time single-season record. He's the player who'd be most affected by a radical scheme change, moving from a traditional defensive end position where he's exclusively in a three-point stance to a stand-up outside linebacker like Dallas star DeMarcus Ware or Green Bay's relentless Clay Matthews.
Frazier said "maybe" when asked if his current roster could be viable in a 3-4 system, but he said such a switch wouldn't come without consultation with key players. Allen, for his part, has no interest in playing without his hand on the turf before the snap.
"They've been so good to me here I don't think they would do it without talking to me. I want to end my career as a defensive end," Allen said.
Greenway could benefit the most from a change, reducing his pass-coverage responsibilities and better maximizing his mobility to rush more often. But even he didn't express any excitement about the possibility, simply saying he'd play whatever scheme he's told to.
"I think we're doing all right with what we've got," defensive tackle Kevin Williams said. "Jared almost beat the sack record. We can't forget that. What would Jared look like as a stand-up end?"
So the Vikings will spend most of their energy determining how to upgrade several positions, after setting a franchise record by allowing opponents a cumulative 68.2 percent completion percentage for the season. They gave up the second-most points in the league and matched their all-time low with only eight interceptions.
E.J. Henderson, the middle linebacker for the last eight years, will be a free agent. So will his younger brother, outside linebacker Erin Henderson, who became a starter this season for the first time. Remi Ayodele, Fred Evans and Letroy Guion are unquestionably replaceable at the nose tackle spot.
Then there is the tattered secondary, which will welcome back next season a 35-year-old Antoine Winfield from surgery to fix a broken collarbone. He'll likely be limited to a nickel package role over the last two seasons of his contract, but he's the only sturdy piece who's certain to return to this group.
"That will get me to year 15. I expect to hang them up after that," Winfield said.
At cornerback, Chris Cook isn't even on Frazier's radar, he said, after putting himself in major trouble with a felony domestic assault charge.
"I can't really factor him into what we're trying to get accomplished," the coach said.
Frazier said he's spoken to Cook a couple of times over the past few months, but they haven't met in person. His next court hearing, scheduled for March 5, will go a long way toward determining his status and future with the team.
"We have no idea what's going to happen. Once there's some clarity, a decision will be made," Frazier said.
Cornerback Cedric Griffin's comeback from his second reconstructive knee surgery in two years didn't go well, and he indicated a desire for a fresh start elsewhere. Frazier said he'll speak to Griffin in the coming weeks and determine whether he can still fit with the Vikings.
None of the players in recapping the season publicly expressed any doubt, though, about the viability of the Tampa Two system.
Defensive end Brian Robison, who finished with eight sacks in an up-and-down first year as a full-time starter, noted the importance of discipline and suggested that too many players tried to overcompensate by straying from their lane to make a big tackle, the downfall of such a gap-control defense. Those are the type of mistakes that happen when the losses pile up.
"Sometimes there is a thin line between doing too much and doing your job. You just have to find that balance," Robison said.
Greenway acknowledged putting too much pressure on himself to perform up to the standard of the five-year contract he signed before the season. His base salary alone was $5.5 million in 2011.
"You've just got to be yourself. I think I realized that three or four weeks in. Just go out there and play and have fun, and things will take care of themselves. I didn't have any interceptions. I'm completely disappointed about that. I didn't make enough big plays to get us enough wins," Greenway said.
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