With the Chiefs finally defeated, the 1972 Dolphins can rest easy.
Josh Allen's spectacular 26-yard run in the fourth quarter gave the Bills a 30-21 victory, handing the Chiefs their first loss since last Christmas.
With just over two minutes remaining, Allen scrambled to second base with four outs, giving the Bills a 23-21 lead.
Buffalo's quarterback found a hole and broke through as four Chiefs defenders missed tackles, then Allen slipped past a fifth man on his way to the end zone.
The last team to beat Kansas City (9-1) was the Raiders, who lost 20-14 at Arrowhead Stadium.
The 1972 Dolphins were the only team to win the Super Bowl undefeated.
