Next man up: Who will replace CMC, Mason in 49ers' starting backfield?

With the 49ers’ top two running back options headed to injured reserve, Matt Maiocco and Jennifer Lee Chan discuss rookie Isaac Guerendo's big opportunity to fill the starting role for the final five weeks of the season. Also, Matt and Jennifer look ahead to next season as performances in the final stretch could affect how the 49ers view their options at offensive line and running back next season. Later, Jennifer and Greg Papa dissect how the 49ers can still make a run at the playoffs, starting with a Week 14 matchup against the Chicago Bears on Sunday at Levi's Stadium.--(2:00) 49ers must retool running-back room with CMC and Mason injured(6:45) Is there a silver lining to CMC injury?(8:00) Guerendo’s great opportunity(11:00) O-line options with Banks possibly headed for big payday(26:00) Guerendo's history as WR up until college will help his adjustment(29:00) Stopping the run will be key to 49ers resurgence this season