Rookie fourth-round pick Isaac Guerendo seemed to be an afterthought in the San Francisco 49ers backfield with Christian McCaffrey back in the fold. Now McCaffrey is on IR and likely out for the season because of a PCL injury in his knee against the Buffalo Bills.

The San Francisco 49ers are falling behind the Seattle Seahawks in the NFC West. Losers of three consecutive contests, it was Seattle’s thrilling Week 11 defeat that sent Kyle Shanahan’s squad on their current winless streak. The 49ers are a last-place 5-7, and suffered a massive blow in Sunday’s embarrassing defeat to the Buffalo Bills.

Guard Ben Bartch and defensive tackle Evan Anderson got their first-ever starts for the 49ers and both played well in snowy Buffalo.

The San Francisco 49ers and fantasy football players who were relying on the NFC West team's running backs are probably all looking for replacement