The Sports Xchange

Minnesota Vikings head coach Mike Zimmer said there are no restrictions for running back Adrian Peterson in Week 1 and beyond.

Peterson takes the field for the first time since last September on Monday night at San Francisco in the final game of the opening week schedule.

Peterson, 30, was held out of preseason games to protect him from senseless injury in meaningless games.

“He’s come in and worked real hard, been a good teammate, obviously he’s a good player,” Zimmer said. “First of all, he’s in great shape. He’s in really, really great shape. We don’t monitor his carries really. He’ll be in there a large percentage of the time.”

Peterson rushed for 2,097 yards in 2012, the last time he came back from a layoff – that one due to injury.

His primary obstacle in the running game will be linebacker NaVorro Bowman, who suffered a severe knee injury in the 2013 NFC Championship game. Zimmer said he watched Bowman closely this preseason and was stunned with his recovery.

“He’s a great player,” Zimmer said. “To go in there and have time off and do the things he did coming back from an injury, we’re kind of hoping Adrian does the same thing when he comes back.”

The 49ers won’t have to contend with starting center John Sullivan, who underwent back surgery Wednesday and was placed on injured reserve with a designation to return – after eight weeks – with 33-year-old veteran Joe Berger expected to start Monday.

The Vikings already lost starting right tackle Phil Loadholt to a season-ending injury in the preseason.