49ers' Christian McCaffrey: Injures knee on SNF

McCaffrey (knee) is questionable to return to Sunday's game against the Bills.

McCaffrey felt something in his leg and slid down immediately after receiving a toss in the second quarter, then got up limping and promptly went to the medical tent. The star running back went to the locker room soon thereafter, per Cam Inman of the Bay Area News Group. McCaffrey had been off to a strong start in snowy Buffalo prior to the injury, rushing seven times for 53 yards and catching two of three targets for 14 yards. Jordan Mason and Isaac Guerendo will comprise San Francisco's backfield in McCaffrey's absence.