Baltimore's leading rusher from its season-opening demolition of the Bills won't return to the field for some time.
NFL Network Insider Ian Rapoport reported earlier Wednesday that Dixon was expected to miss several weeks. Dixon can be designated to return from IR after Week 8.
In a corresponding move, Baltimore signed running back De'Lance Turner to the active roster.
Dixon paced the Ravens' ground attack against Buffalo with a game-high 44 rushing yards and a score. Baltimore's other tailbacks, Javorius Allen and Alex Collins, combined for 30 yards and two touchdowns on 11 carries.
Dixon's injury is an unfortunate setback for a promising player with terrible injury luck. The running back has missed 20 of a potential 33 regular-season games due to knee injuries or suspension. He sat out the entirety of the 2017 campaign.
At times on Sunday, Dixon looked like the Ravens' most explosive back, offering a tantalizing complement to Baltimore's remade receiving corps. Now the Ravens will have to regroup quickly with a clash with the division rival Cincinnati Bengals approaching on Thursday night.