“It means so much to me to do something like this for Kansas City and all its fans in all the states around Kansas City,” said Mahomes, who came to the Chiefs in 2017 after a daring trade put Kansas City in a position to select him in the college draft. “The Chiefs brought me here and believed in me from the beginning. And all I’ve wanted to do since then is to reward their faith in me by winning a Super Bowl.”

Deep into the second half, it looked as if Mahomes would have to wait another season to reach that goal.

With five minutes remaining in the third quarter, he tried to force a pass that had to travel nearly 30 yards across the middle of the field and past a handful of 49ers defenders on its way to the intended receiver, Tyreek Hill. San Francisco linebacker Fred Warner cut a few yards in front of Hill and easily intercepted the pass. The 49ers soon led, 20-10.