Minnesota Vikings star running back Adrian Peterson left in the third quarter against Green Bay with an injured right knee.

Peterson was injured after a 5-yard run late in the third quarter. He was not able to put any pressure on his leg has he hobbled off the field and needed to be helped back to the locker room for further testing. Upon arriving in the locker room, Peterson was quickly ruled out for the rest of Sunday night.

Peterson tore the ACL in his left knee in the second-to-last game of the 2011 season.

He was on crutches after the game, wearing a brace on his right leg. Coach Mike Zimmer said he was told the injury had “calmed down.”

“He might miss a week. I don’t know if he will or not,” Zimmer said.

Peterson finished the game with just 19 yards on 12 carries against the Packers.