Denver cornerback Bradley Roby returned Jamaal Charles' second fumble 21 yards for a touchdown with 27 seconds left, completing a stunning comeback in the closing minute for a 31-24 victory - the Broncos' seventh straight over their AFC West rivals.

Peyton Manning threw for 256 yards and three scores, the last to Emmanuel Sanders with 36 seconds left as the Broncos (2-0) appeared to force overtime. But on the next play from scrimmage, with the Chiefs (1-1) also eyeing overtime, Charles was stripped by Brandon Marshall and the ball bounced right into Roby's hands.

The dramatic about-face came after Knile Davis gave Kansas City the lead with 2:27 left on an 8-yard run, raising hope among a sellout crowd that the Chiefs might finally end some curses.

Instead, Denver won its 13th straight division road game, breaking a tie with the San Francisco 49ers (1987-90) for most in NFL history. And for one night, Manning quieted his growing doubters by improving to 14-1 in his career against the Chiefs.

Charles finished with 125 yards rushing and a touchdown, but he will only remember his fumbles - one in the red zone early in the game, the other deep in his own territory late in the game.

Alex Smith threw for 191 yards for Kansas City, but also had two passes picked off.

Manning threw a pick-six of his own, but he responded when it mattered the most.

The Broncos took over at their own 20 after Davis had given Kansas City the lead, and the seven-time All-Pro marched them calmly down field. Manning found Demaryius Thomas for three long receptions to get deep into Chiefs territory, then hit Sanders with a strike over the middle on third-and-10 from the Chiefs 19 for the touchdown that kept Denver alive.