Patrick Mahomes accepted responsibility after the Kansas City Chiefs suffered a dramatic 27-24 overtime defeat to the Cincinnati Bengals in the AFC Championship Game.

The Chiefs were heavy favourites coming into Sunday's game at Arrowhead Stadium and quickly built up a 21-3 advantage.

Despite a Bengals response, Kansas City were still 11 points clear when they had the ball on the Cincinnati one-yard line just before half-time.

But they misjudged the clock and failed to add to their advantage, as time expiring after a completed pass to Tyreek Hill meant they could not even kick a field goal.

The Bengals then rallied in the second half to move ahead 24-21 and while the Chiefs were able to get the game to overtime, it was Cincinnati who came out on top.

Just 34 yards, two first downs and an interception from Mahomes came from the first five Kansas City drives in the second half as the offense went completely flat, costing the hosts victory.

"When you're up 21-3 in a game, you can't lose it, and I put that on myself," Mahomes said.

"I was supposed to throw the ball away [in the play before halftime]. I got a little greedy there and tried to give it to Tyreek and get a touchdown, they had two people out there. 

"In the long run of things, it looks bad, but if we had another chance, I'd go for another play again.

"There was a few misreads here and there. There was guys that were open and I didn't hit at the right time or I passed up on something shorter that I wanted to get something deeper down the field. 

"When you're playing a good team and you don't hit what's there and you try to get a little bit more than what's necessary it kind of bites you in the butt, I guess you would say. 

"We were playing so well in the first half and in the second half, we were just off a tick and that's all it takes to lose a football game."

The Chiefs have been to four straight championship games with Mahomes as starter. Their two defeats, in this game and to the New England Patriots in 2018, both came in overtime.

Mahomes added: "A few plays here and there we could have four chances at the Super Bowl.

"You can't let this end what we have here, you have to make sure you continue to battle, continue to get better and try to find ways to win Super Bowls.''

Defeat cost the Chiefs a chance to reach a third straight Super Bowl.

Head coach Andy Reid was reluctant to blame star quarterback Mahomes, who was intercepted by B.J. Hill in the third quarter before throwing another pick to Vonn Bell in OT.

"Patrick's a great player, he was trying to make a play," he said when asked if Mahomes had pressed too much as the Chiefs started to lose their lead.

"I have got to do a better job at giving him things that he can make plays with. I can do a lot better in that area. 

"I could've given him other things to work with, better things, better plays to work with."

Of the Chiefs' mistake at the end of the first half, Reid added: "I was hoping we could get the ball in the end zone.

"I probably gave him the wrong play first of all. To start with, I could've given him something better than that, where the play was open in the end zone, and then we wouldn't have had to go through that. 

"I'll take responsibility for that one."

Mahomes completed 26 of 39 attempts and threw three touchdowns as well as his two picks.