The Bengals have downgraded Mixon (concussion) to out for Sunday's game against the Vikings, Geoff Hobson of the Bengals' official site reports.
The Bengals were clearly anticipating this designation, as they promoted fellow rookie running back Jarveon Williams from the practice squad earlier in the day to offer additional depth at the position. Mixon's full practice participation Friday offered some hope that he would be able to return from a one-game absence, but he was unable to receive clearance from an independent neurologist in advance of the Week 15 matchup. With Mixon sidelined again, Giovani Bernard will presumably continue earning the majority of snaps in the Bengals' backfield, making him a solid option in most fantasy settings.