An MRI on Monday revealed that Dunbar had sustained a torn ACL, ending his season after just four games.
Used in tandem with Joseph Randle out of the backfield, Dunbar rushed for 67 yards on five attempts this season and caught 21 passes for 215 yards, second-most on the team.
Dallas will take on the New England Patriots on Sunday at 4:25 p.m. ET.
- Xandria James