Quarterback Mahomes, 24, had endured a difficult evening under the pounding pressure of the 49ers and looked set to miss out on the big prize.

But then, with his side 20-10 down heading into the fourth quarter, last year's MVP found two superb throws on third down to continue a season of comebacks as the Chiefs scored 21 unanswered points in four minutes and 57 seconds to take home the Vince Lombardi Trophy.

Damien Williams' second touchdown of the final quarter put the gloss on the scoreline as the Chiefs capped their wonderful late rally before celebrating a famous win in emotional scenes.

"We never lost faith. Everybody on this team, no one had their head down and we found a way to win in the end," Mahomes, who was named Most Valuable Player, said in a TV interview as his team-mates celebrated under a cloud of confetti.

"The defence got some big stops for us and we found a way to win. Coach [Andy] Reid told me 'keep firing, keep believing' and he gave me a lot of confidence to go out there no matter what.

"The 49ers have an amazing defence, one of the best defences I've played against so far and I'm just glad our guys kept fighting. This team has heart, coach pushes us to be the best we can be. We did it baby!"

Throughout a forensic week of pre-match questioning, Mahomes had found himself under scrutiny like never before. After another season of brilliance, including no-look passes and a touchdown pass with his left hand, he found himself in the bizarre position of being compared with some of the all-time greats of the game while also being asked if he may choke on the biggest stage.

After three quarters of an excellent game those questions seemed reasonable enough - despite the superstar quarterback running in the game's opening score.

Mahomes only threw five interceptions in the whole of the regular season but coughed up two in back-to-back drives as the incessant pressure from the 49ers defence took its toll and the team from the west coast looked set for a record-equalling sixth win.

The Chiefs were up against it, 20-10 down, but found resilience in the form of their star man and the fact that they had already won twice on this post-season run after being at least 10 behind.

At third & 15 on their own 35-yard line, Mahomes evaded a tackle and launched a 44-yard bomb downfield to find Tyreek Hill and start the ball rolling.

That turned into a touchdown for Travis Kelce - after another huge throw on third down from Mahomes - to cut the deficit to three.

After the 49ers were shut out in response, Mahomes found Williams for a score which had to be reviewed, but was given to put the Chiefs ahead.

Williams then sprinted in for a second to cap a memorable win, as the 49ers crumbled.

Richard Nixon was in the White House, Diana Ross was still in the Supremes and Paul McCartney hadn't quit the Beatles last time the Chiefs won the Super Bowl.

And McCartney was among the galaxy of stars in the house to see that run come to an end in Miami on a superb Sunday night.