The team reportedly believes that Johnson suffered a knee sprain and not an ACL tear, as per Rapoport.
The rookie left late in the third quarter and had 87 yards on 15 carries with one touchdown before suffering the injury.
Johnson was selected No. 43 overall in this year's NFL draft. He's cleared a role for himself in a cluttered Lions backfield, accumulating 641 rushing yards and 213 receiving yards with four total touchdowns this season.