The 49ers used a devastating defense to hold down the Bears in a 32-7 win. Aldon Smith had five-and-a-half sacks for a Niners defense that forced two turnovers and allowed just 143 yards. San Francisco's backup quarterback Colin Kaepernick was brilliant in his first-career start, throwing for 243 yards with two touchdowns. Frank Gore added 78 yards on the ground while Vernon Davis caught six passes for 83 yards and a touchdown. San Francisco moved to 7-2-and-1 with the win. Chicago also started a backup quarterback in Jason Campbell, who threw for just 107 yards with a touchdown and two interceptions. Matt Forte managed just 63 yards on 21 carries for Chicago, which fell to 7-and-3. Brandon Marshall caught the lone touchdown for the Bears.