Jim Langer lay on his bed at the Waldorf Astoria on a chilly New York morning in December 1972, waiting for the Miami Dolphins team bus to leave for Yankee Stadium.
"You know we haven't lost yet?" quizzed room-mate Bob Kuechenberg. "Maybe it wouldn't be such a bad thing if we lost a game once…. So we don't have that jinx on us."
Langer and Kuechenberg were good friends and had both been part of the Dolphins squad that suffered a gut-wrenching defeat by the Dallas Cowboys in the Super Bowl 11 months earlier.
But this particular mid-morning chat in the Big Apple was by no means serious. The Dolphins had already secured a play-off spot by winning their opening 12 matches and coach Don Shula, himself the victim of two Super Bowl losses, would never allow his side's standards to slip.
Later that afternoon, the New York Giants became yet another scalp in an unprecedented perfect season.
Shula's invincible Dolphins would go on to win the Super Bowl that year with an undefeated 17-0 record. It had never been achieved before and - as the National Football League enters its 100th season - has never been achieved since.
"Man, it's been a long time," recalls Langer. "Nobody thought we would be talking about this 40-something years later.
"I mean, hell, I just lost Bob earlier this year. I roomed with him for 10 years. That was a very special team. It became a family."
The '72 Dolphins' legacy has outlasted some of the players that made it possible - Kuechenberg died aged 71 in January and Hall of Famer Nick Buoniconti passed away in July at the age of 78 - while a selection of those who remain still raise a toast together when the last undefeated team loses each season.
Their record as the only Super Bowl champions to record a perfect NFL season lives on. This is the story of how a bunch of "cast-offs" who were working part time, with a quarterback signed for $100, rallied together to achieve sporting greatness.
The season before coach Shula's arrival in 1970 the Dolphins finished the campaign with just three victories and 11 defeats. They'd won only four games a year on average in the franchise's short history prior to that.
Paul Warfield, then with the Cleveland Browns, says Miami were regarded as a "misfit, loser, ragtag" organisation whose players were "not disciplined" and "not committed".
Everything would change.
Former Baltimore boss Shula sprung a shock trade for wide receiver Warfield and began cobbling together the "misfits" who had been cut or released by other teams.
"We were a bunch of cast-offs," laughs Langer, himself signed as a free agent from the Browns.
"It was hard when Shula first got there. He put 22 new players on the roster and a lot of the older players just didn't buy into that kind of work ethic.
"It literally became your life. But that's what it takes, that is just how Don Shula wanted to practise."
In his second season in charge Shula guided the Dolphins to the first Super Bowl appearance in their history, but on an unusually cold night in New Orleans in January 1972 they were beaten by the Dallas Cowboys. Shula and his players were devastated.