Mitchell (knee) doesn't have an injury designation for Sunday's game against the Rams, Nick Wagoner of ESPN.com reports.
Mitchell returned from a three-game absence last week and took 23 touches for 130 yards and a TD in the 49ers' 23-7 win over Houston. He should be busy again Sunday, regardless of whether Jimmy Garoppolo (questionable/thumb) or Trey Lance is starting at quarterback. In his first matchup with the Rams, back in Week 10, Mitchell took 27 carries for 91 scoreless yards and finished without a target in a 31-10 win for the Niners.