Mostert (knee) is active for Thursday's game at Arizona.
Mostert and Matt Breida (ankle) followed an LP/DNP/LP practice regimen Monday through Wednesday, but the limitations won't hurt their ability to suit up Week 9. Mostert has been the 49ers' clear No. 3 running back this season behind Breida and Tevin Coleman, averaging 17.6 snaps on offense and 8.3 touches per game.