Adrian Peterson won't be eligible for reinstatement until April 15, but Mike Zimmer wants the Vikings to keep the running back next season.

The 2012 NFL MVP was suspended by the league after pleading no contest to a misdemeanor of recklessly injuring his 4-year-old son. Peterson played in only the season opener, but he left a lasting impression on the first-year head coach.

"Adrian was always great with me," Zimmer said. "I think he's a good person. I think obviously he's a great running back, and if it works out that way and things work out and he gets his life in order — that's the most important thing, he gets his life in order, he gets the opportunity to come back — then I will be in his corner whenever the decision is made."

Peterson turns 30 in March and will be due $15.4 million next season if the two sides do not restructure his contract. Zimmer hasn't talked to General Manager Rick Spielman about Peterson's situation yet, but he hopes the NFL will resolve the manner quickly so the Vikings can plan their offseason accordingly. The free agency period begins on March 10, nearly a month before Peterson could be reinstated.

"He would add value to any team," Zimmer said. "The kid's a heck of a football player. I just was watching our offensive tape — I was starting to go back right now with evaluating our players and I was starting with the offense in St. Louis — so it was a good recollection on my mind right now of him."

Keeping the door open

Linebacker Chad Greenway wants to return to the Vikings for his 10th season, and Zimmer believes he can serve as a starter. Greenway, who turns 32 in January, will be owed $7 million in base salary next season.

Vikings coach Mike Zimmer and Adrian Peterson.

"I love Chad," Zimmer said. "You'd have to ask him, but I think even at his stage in his career, he probably learned some things this year. And we asked him to do a lot of different things he probably hasn't done before. He's the kind of guy that we like to have."

Greenway was inactive four times because of rib and knee injuries.

"I feel pretty good even though I missed the first games I've missed in a long time," Greenway said. "The rib injury was really kind of a fluky deal, and obviously this knee thing would have put anybody out. … I don't feel like I've become injury-prone or my age has caught up to me anyway. I feel like I can continue to play somewhere — hopefully here."

A different tack

Left tackle Matt Kalil will change his offseason priorities this season and focus on technique. Last year, he spent the majority of his time strengthening his right knee following a procedure. He felt he was playing catch-up on the fundamentals throughout training camp and into the start of the season.

"It's not fun getting off to a slow start and then everyone starts to pile on top of you and all of that pressure. But I think I bounced through that and fought through all that criticism to come out on the other end on a high note," he said. "I've faced some pretty good pass rushers these last few weeks, and I thought I played pretty well."

Kalil allowed only one sack over the final six games after allowing 11 in the first 11 games

Captain's choice

Cornerback Captain Munnerlyn didn't play anywhere near his expectations during his first season with the Vikings after five years in Carolina. "It was a new system to me and a new coaching staff, new teammates, but it's no excuse," Munnerlyn said. "I'm a pro, so … I think I guarantee I have a better year. I would say I didn't listen. I just went out there and tried to make a couple of plays my way and sometimes it didn't work."

Sticking around

The Vikings signed all nine players on their practice squad to reserve/future contracts: linebacker Justin Anderson, wide receiver Kain Colter, quarterback Pat Devlin, defensive tackle Isame Faciane, wide receiver Donte Foster, center Zac Kerin, guard Jordan McCray, tight end Ryan Otten and running back Dominique Williams.