Davis quickly got to his feet but appeared dazed as he came off the field. Chancellor was flagged for unnecessary roughness, though replays showed the hit was clean.
It was all part of a Murphy's law kind of first half for the 49ers, who lost Davis, gave up a touchdown off a blocked field goal and went into the locker room down 28-6.
The 49ers lost another offensive weapon in the third quarter, when wide receiver Mario Manningham left the game with a left knee injury. Manningham grabbed at the knee after being gang-tackled, losing a fumble in the process. Manningham did not return, and Comcast SportsNet Bay Area's Matt Maiocco reported that 49ers coach said X-rays on the receiver's knee were negative. Manningham did leave the locker room on crutches, though.
The 49ers can't get on the team plane fast enough.
Follow Dan Hanzus on Twitter @DanHanzus.