Starting with the ball at their own 8-yard line, the 49ers got going with a Brock Purdy scramble that gained 9 yards. But then San Francisco gained 15 more with a horse collar penalty on linebacker Nick Bolton, who was attempting to get Purdy out of bounds. That put San Francisco on its own 32.
Following short runs by Deebo Samuel and Christian McCaffrey, Purdy tried to evade the pass rush by escaping the pocket to his left. But safety Justin Reid and defensive end George Karlaftis were there to meet him and brought the quarterback down for a 4-yard sack.
Kansas City will start its next drive from the 20-yard line.