LOS ANGELES -- Patrick Mahomes threw for three touchdowns as the reigning NFL champion Kansas City Chiefs overpowered the Buffalo Bills 38-24 to book a second straight Super Bowl appearance on Sunday.

Mahomes set up a showdown against Tom Brady and the Tampa Bay Buccaneers next month as the Chiefs' superior offensive power proved decisive in the AFC Championship decider at Arrowhead Stadium.

Chiefs quarterback Mahomes finished with 325 passing yards with 29 completions from 38 attempts with no interceptions.

The Bills had got off to a dream start, taking an early 9-0 lead after a Tyler Bass field goal and a touchdown by Dawson Knox after a muffed punt return by chiefs receiver Mecole Hardman.

But the Chiefs moved through the gears thereafter with Mahomes showing no sign of the concussion that had knocked him out of last week's divisional round victory over the Cleveland Browns.

Hardman made amends for his costly punt fumble after gathering a short pass from Mahomes for a three-yard touchdown to complete a 14-play 80-yard drive to make it 9-7.

Hardman then produced an electric 50-yard rush on the Chiefs' next possession to take Kansas City deep into Bills territory.

Four plays later, Darrel Williams rushed over from six yards to put the Chiefs 14-9 ahead after Harrison Butker's extra point.

With the Bills struggling to generate any momentum on offense, the Chiefs were soon threatening again.

Another smooth drive by Mahomes set up running back Clyde Edwards-Helaire from the one-yard line for a touchdown that was all too easy.

Bass added a second field goal to cut the score to 21-12 at the break but the Chiefs restored their 12-point cushion at 24-12 in the third quarter after Butker's second field goal of the game.

Buffalo were forced to settle for another field goal on the next drive that made it 24-15.

But the Chiefs were soon back in the red zone after Tyreek Hill's blistering 71-yard run from a short pass from Mahomes.

That left the Chiefs at Buffalo's four-yard line, and Mahomes flipped a cheeky pass to tight end Travis Kelce for a touchdown that took the score to 31-15 after Butker's extra point.

Kelce's second touchdown took the Chiefs 23 points clear at 38-15 and seemingly cruising.

But Buffalo quarterback Josh Allen hit Isaiah McKenzie for a seven-yard touchdown to make it 38-21, and the Bills then recovered an onside kick to raise hopes of an unlikely comeback.

Allen's frustration boiled over, though, after he was sacked on the ensuing drive, tossing the ball at the Chiefs Alex Okafor to trigger an unseemly mass scuffle.

© Agence France-Presse

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