Fifty years later, the 1972 Miami Dolphins remain the only team to enjoy a perfect season in NFL history.
On Monday night, the Washington Commanders ensured those Dolphins' special place in league lore by finally handing the Philadelphia Eagles their first loss of the 2022 season.
As has long been customary, members of the '72 Fins marked the final unbeaten team's first defeat with a little celebration.
Among the revelers was Hall of Fame fullback Larry Csonka, who tweeted a photo of himself toasting the Commanders with what appeared to be an adult beverage.
"Thank you #WashingtonCommanders," the tweet said. "As in 2020 when you knocked out the Steelers I'm a Washington fan tonight! #WASvsPHI #ESPN #72Dolphins #Undefeated"
The loss dropped the Eagles to 8-1, while the Commanders improved to 5-5.
Of course, even if the Eagles had won, they would still have a long way to go before flirting with immortality -- eight regular-season games plus three postseason contests. That would be 20 consecutive wins, if you're keeping score at home.
The '72 Dolphins won 17 consecutive games -- 14 in the regular season and three in the playoffs. That mark was subsequently surpassed by the 2007 Patriots, who won 18 in a row after going 16-0 in the regular season and winning their first two postseason games before falling to the Giants in Super Bowl XLII.
Further illustrating just how much the sport has changed in half a century, Csonka's position, fullback, has largely been phased out of the game, with many teams not even bothering to carry one on the roster. Few of the remaining fullbacks are on the field regularly, and they usually see minimal touches.
In any event, the '72 Dolphins remain the only team who can lay claim to the title of "perfect season."