Mitchell (knee) is listed as inactive Sunday versus the Cardinals, Lindsey Pallares of the 49ers' official site reports.
Mitchell was a late addition to the 49ers' Week 4 injury report after he was tripped up during Thursday's practice, as coach Kyle Shanahan told Nick Wagoner of ESPN.com on Friday. The resulting knee injury is concerning considering Mitchell sustained MCL sprains to both of his knees last season, which allowed for only five regular-season appearances. The severity of the current issue isn't known, but Mitchell will yield the No. 2 RB gig behind Christian McCaffrey in San Francisco to Jordan Mason for at least one contest.