The Vikings placed Adrian Peterson on injured reserve Friday.
Peterson underwent surgery Thursday to repair a torn lateral meniscus in his right knee. It's still possible Peterson returns this season as each NFL team is allowed to reinstate one player from injured reserve after eight weeks.
The earliest the Vikings could bring back Peterson onto the active roster is Week 11 in the middle of November, however he's expected to be sidelined longer after choosing to have his meniscus tear fully repaired. Teams no longer need to designate which player they'd like to return from injured reserve.
Through two games, Peterson gained 50 yards on 31 carries before injuring his knee against Green Bay.
Peterson, 31, is under contract through next season, though it's an option year with a cap hit of $18 million.
After the move, the Vikings sit with one open roster spot.
