Patrick Mahomes passed for 325 yards and three touchdowns as the Kansas City Chiefs became back-to-back as AFC champions, by downing the Buffalo Bills 38-24 in Kansas City.

After getting cleared from concussion protocol Friday, Mahomes still played with turf toe on his left foot but completed 29 of 38 attempts as the Chiefs gained an opportunity for a title defence.

Kansas City will attempt to become the first back-to-back NFL champion sincethe 2003-04 seasons (New England Patriots) when they meet the Tampa Bay Buccaneers on 7 February in Super Bowl LV.

The Bucs beat the Green Packers 31-26 for the NFC title and will get to stageSuper Bowl LV at home. Tom Brady will make his 10th Super Bowl appearance against a Chiefs team that went undefeated on the road this season.

The Chiefs went three-and-out on their opening possession, then overturned a 9-0 deficit with second-quarter touchdown drives of 82, 80 and 77 yards.

Taking away a one-play kneel down to end the first half, Kansas City scored on six straight possessions while going 5-for-5 on touchdowns in the red zone.

Tyreek Hill raced 172 yards on nine receptions, including a 71-yard gain. Travis Kelce added 13 catches for 118 yards and two scores as the Chiefs amassed 439 yards.

Buffalo's Josh Allen completed 28 of 48 passes for 287 yards and two touchdowns, while rushing for 88 yards, but fourth-quarter interceptions by Rashad Fenton and Bashaud Breeland (on a two-point conversion attempt) proved disastrous.

The Bills converted just 2 of 5 red zone opportunities into touchdowns and settled for four field goals from Tyler Bass. Cole Beasley grabbed a team-high seven catches for 88 yards.

The game ended with chippy altercations that drew offsetting penalties.

The Bills converted Taiwan Jones' recovery of a muffed punt by Mecole Hardman into a 3-yard touchdown pass from Allen to Dawson Knox for their 9-0 lead.

The Chiefs recovered to build a 21-12 halftime margin as Hardman atoned for his mishandled punt. He grabbed a 3-yard touchdown from Mahomes with 14:16 left in the half before beginning Kansas City's next drive with a 50-yard end around.

The Chiefs tacked on touchdown runs of 6 and 1 yards from Darrel Williams and Clyde Edwards-Helaire for a 21-9 lead.