Christian McCaffrey won't play Week 18

49ers RB Christian McCaffrey (calf) will not play vs. the Rams this weekend, HC Kyle Shanahan confirmed Monday. Shanahan called McCaffrey's injury a "mild calf strain." It's unclear if CMC would be able to play if this game meant something to San Francisco, but he was never going to suit up with the NFC's No. 1 seed clinched. He'll get three total weeks to heal up before the 49ers' playoff opener. We'll see about the team's backfield plans this weekend. RBs Elijah Mitchell and Jordan Mason are on the active roster, with RB Ty Davis-Price on the practice squad.