Quarterback Patrick Mahomes led the Kansas City Chiefs to their first Super Bowl title since 1970 after a wild comeback saw them overcome the San Francisco 49ers in a thriller in Miami.
Mahomes and running back Damien Williams dragged the Chiefs back from a seemingly insurmountable 10-point deficit with less than nine minutes left in the game to eventually prevail 31-20 and lift the title.
KC, who ended their 50-year drought without the Vince Lombardi trophy, won a second title and left San Francisco and their coach Kyle Shanahan with another heartbreaking loss in the big game.
MVP Mahomes, who had starred in similar comebacks in the post-season, threw two interceptions but delivered when it mattered most, throwing TDs to Travis Kelce and Williams in the fourth quarter to take the lead.
"I didn't play to my liking in the third quarter but the guys believed in me, gave me confidence and we kept fighting and we found a way to win it in the end,'' Mahomes said.
"It's amazing just to be here. It's surreal. We'll enjoy this for a long time.''
Williams' second score iced it and gave head coach Andy Reid his first Super Bowl win.
Scores from Kyle Juszcyk before the break and Raheem Mostert afterwards appeared to have put the Niners on course for a record-equalling sixth title and left the Chiefs in a 20-10 hole.
But then Mahomes threw deep to a wide open Tyreek Hill for 44 yards. Kansas City then scored a touchdown four plays later, and quickly forced a punt.
Mahomes then conjured more magic to hit Sammy Watkins for 38 yards to set up a five-yard scoring reception by Williams that put his team ahead 24-20 with 2:44 to go.
The 49ers then reached midfield as they aimed for a miracle, but Jimmy Garoppolo was sacked by Frank Clark on fourth down.
Williams then sauntered in from 38 yards to spark jubilant scenes in Hard Rock Stadium and back in Missouri.
It was a fairytale ending to the season for the 27-year-old, who entered the NFL as an undrafted free agent with Miami in 2014, finishing the Super Bowl with 104 yards on 17 carries, as well as 29 receiving yards.
"You dream of this moment," Williams said. "It doesn't feel real yet.
"I entered the league undrafted. I had to fight my way in. The Chiefs told me I had to work to make the team. Hearing the doubt, I bring a lot of attitude to this game."
Quarterback Mahomes added: "We never lost faith. Everybody on this team, no one had their head down and we found a way to win in the end. The defence got some big stops for us and we found a way to win.
"Coach 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. The coach pushes us to be the best we can be. We did it, baby!"
Meanwhile, San Francisco coach Shanahan remained upbeat despite the loss, which leaves the 49ers without a Super Bowl title to their name since 1994.
"Win or lose, today doesn't change how I feel about our team,'' Shanahan said.
"I'm proud of the guys, what they did all year. I'm proud of what they did today."
The Niners chief did fire a parting warning to the rest of the league, insisting: "We'll lick our wounds, we'll get over this and we'll be fired up for next year."