Mason took 13 carries for 78 yards and received no targets in Sunday's 35-10 loss to Buffalo.
Mason saw a spike in carries in Sunday's blowout loss after starter Christian McCaffrey (knee) limped off the field at halftime and did not return. The capable backup looked the part in a run-heavy game plan dictated by snowy conditions. McCaffrey's status will be clarified as the practice week progresses, but savvy fantasy managers should already be putting claims in for Mason after the work he put in as fill-in starter earlier this year. It is worth mentioning that Mason also left Sunday's contest to be evaluated for a concussion, but he was subsequently cleared and finished without issue, according to 49ers team reporter Lindsey Lares.