CJ West engulfs Rivers, notching the first sack of 49ers-Colts matchup on 'MNF'

San Francisco 49ers defensive tackle CJ West bursts through the double team to take down Indianapolis Colts quarterback Philip Rivers for an 8-yard sack.

San Francisco 49ers linebacker Dee Winters ices Indianapolis Colts with huge 74-yard pick-six against quarterback Philip Rivers.

Indianapolis Colts cornerback Camryn Bynum takes advantage of the missed catch by San Francisco 49ers wide receiver Kendrick Bourne to secure an interception.

San Francisco 49ers defensive tackle Alfred Collins sacks Indianapolis Colts quarterback Philip Rivers, who fumbles the ball that is recovered by the Colts 5-yard line.

San Francisco 49ers QB Brock Purdy notches his fifth TD of the night as he finds RB Christian McCaffrey for the score.

San Francisco 49ers running back Christian McCaffery bolts out of the backfield for a 24-yard gain.

San Francisco 49ers quarterback Brock Purdy completes a 17-yard pass to wide receiver Jauan Jennings.

Indianapolis Colts running back Jonathan Taylor sneaks into the end zone for a 1-yard touchdown.

Indianapolis Colts quarterback Philip Rivers completes a 19-yard pass to tight end Tyler Warren.

San Francisco 49ers kicker Eddy Piñeiro makes a 38-yard field goal.

San Francisco 49ers wide receiver Jauan Jennings leaps to secure 19-yard pass from quarterback Brock Purdy.

Indianapolis Colts kicker Blake Groupe makes a 51-yard field goal.

San Francisco 49ers quarterback Brock Purdy completes a 3-yard touchdown pass to wide receiver Jauan Jennings.

San Francisco 49ers quarterback Brock Purdy rolls out of the pocket to locate tight end George Kittle for a 15-yard gain.

San Francisco 49ers tight end George Kittle catches a 15-yard pass from quarterback Brock Purdy.

San Francisco 49ers kicker Eddy Piñeiro just barely misses a 64-yard field goal attempt that bangs off the crossbar.

Indianapolis Colts kicker Blake Grupe drills a 39-yard field goal.

San Francisco 49ers kicker Eddy Piñeiro makes a 25-yard field goal.

San Francisco 49ers wide receiver Kendrick Bourne secures $500,000 contract bonus after 11-yard gain following a pass from quarterback Brock Purdy.

San Francisco 49ers tight end George Kittle grabs a 17-yard pass from quarterback Brock Purdy.

San Francisco 49ers quarterback Brock Purdy completes a 23-yard pass to wide receiver Skyy Moore.

San Francisco 49ers tight end George Kittle catches an 11-yard touchdown pass from quarterback Brock Purdy.

San Francisco 49ers running back Christian McCaffery rushes for an 18-yard gain.

Indianapolis Colts quarterback Philip Rivers tosses a 17-yard dime to wide receiver Alec Pierce in the back of the end zone for a touchdown.

Indianapolis Colts quarterback Philip Rivers completes a 17-yard pass to wide receiver Alec Pierce.