Harrison Butker kicked three field goals, including a go-ahead 20-yarder with 5:57 left, and Leo Chenal blocked a 35-yard field goal as time expired as the host Kansas City Chiefs rallied to defeat the Denver Broncos 16-14 on Sunday to remain unbeaten.

Patrick Mahomes threw for 266 yards and a touchdown for the Chiefs (9-0), who exhaled after a late blunder put them in a precarious position.

Butker, who also connected on field goals of 36 and 28 yards, sent the kickoff after his final make of the afternoon out of bounds, giving the Broncos the ball at their own 40-yard line.

Denver (5-5) capitalized on favorable field position and was set up for a chip shot to win the game, but Chenal and the special teams preserved the victory by blocking Wil Lutz’s field-goal attempt.

A defensive turnaround spurred the Chiefs and helped offset inconsistency in the red zone. After allowing 192 yards in the first half, Kansas City yielded just 68 yards in the second half.

Denver took a 14-10 lead into halftime, moving the ball quickly and effectively during a pair of second-quarter touchdown drives.

Bo Nix, who was 14-for-20 passing for 160 yards in the first half, ended both possessions with touchdown passes, connecting with Devaughn Vele for 6 yards and with Courtland Sutton for 32.

Nix finished 22 of 30 for 215 yards. Audric Estime gained 53 yards on 14 yards and Sutton had six caches for 70 yards.

Sutton’s TD with 6:39 to go in the second quarter put the Broncos ahead 14-3, marking the largest deficit the Chiefs have faced during their 15-game winning streak that includes the postseason.

KC responded with a 14-play, 65-yard touchdown drive, capped by a 2-yard scoring pass from Mahomes to Travis Kelce, who had eight catches for 64 yards.

Kareem Hunt had 100 yards of total offense for the Chiefs, including 65 yards on seven catches.

Attempting to match a career long with a 60-yard field goal in the closing moments of the first half, Lutz was well short. Mecole Hardman retrieved the attempt deep in the end zone and returned it 57 yards to the Chiefs 48 as time expired.

Denver finished with four sacks.

Chiefs left tackle Wanya Morris left the game with a knee injury in the second half but returned in the fourth quarter.