They were quickly becoming the NFL's "it" team, led by a seemingly impenetrable defense and a mistake-free offense.
That defense had slowly started to crumble. That offense is no longer playing so flawlessly.
Far from it.
It was the third straight loss for the Chiefs (9-3), and the second to Denver (10-2) over that span.
That means the Broncos hold the tiebreaker in the division race, and Kansas City is virtually assured of playing a first-round playoff game on the road.
Smith threw for 293 yards and two touchdowns for Kansas City, while Knile Davis returned a kickoff 108 yards for another score. Charles finished with 93 yards rushing.
"We figured they would have some type of surge early and I loved the way our guys responded," Del Rio said. "It puts us in first place and now we'll go welcome Coach Fox back."
Denver won despite missing a slew of injured players, including three starters on defense and tight end Julius Thomas, who has developed into one of Manning's favorite red-zone options.
No need to worry. Decker more than shouldered the burden.
Manning has 41 TD passes, breaking his franchise record of 37 set last season.
"Sometimes, when you play a team close to back-to-back, there are some ideas that are fresh in your mind," Manning said. "We thought there were some chances to get down the field in that first game that we never got to. We wanted to get to some of those plays."
Still, Kansas City seemed to have more energy in the first half.
That's went Denver scored 28 unanswered points.
Notes:Chiefs TE Anthony Fasano (concussion) and LT Branden Albert (knee sprain) left the game and did not return. ... Charles became the first Chiefs RB with four 1,000-yard rushing season. ... It was Decker's sixth career 100-yard game. ... Denver has won 10 straight vs AFC West. ... Manning went over 4,000 yards passing for the 13th time. ... KC has allowed 1,118 yards and nine TDs passing during its three-game skid.
Copyright 2013 by The Associated Press