Long before Bill Belichick spawned a football dynasty with the New England Patriots, he was supposed to be Bill Parcells' successor with the New York Jets.

The Jets were intent on promoting Belichick to the head coaching position at the beginning of the new millennium. Instead, Belichick resigned before coaching a single game.

Belichick called the moment one of the “defining” and “great” moments of his career which, in hindsight, is most certainly true. Here's the evidence:

Belichick's Jan. 4, 2000 press conference is one of the most infamous moments in recent NFL history.

The Jets were coming off an 8-8 season just one year after reaching the AFC Championship Game in 1998.

But Belichick, in a strange series of events, abruptly decided he would not take the head coaching position in New York. He wrote his resignation on loose-leaf paper before holding a press conference.

There remains a certain aura of mystery and even conspiracy surrounding Belichick's resignation, as ESPN's Rich Cimini detailed in January:

On some level, Belichick's departure is still shrouded in mystery. Some people, mainly in the Belichick camp, refuse to this day to talk about what they know. Responding to ESPN's interview requests, they acted as if they were being asked to snitch on a mob boss.

“Doubt I'll touch that one!” one longtime Belichick confidant said in a Facebook message to ESPN.

Of course, there is little reason for Belichick to regret his decision.

The legendary head coach actually went 5-11 in his first season with the Patriots and — given past failings in Cleveland — even faced questions about his job.

However, Belichick and a sixth-round draft pick by the name of Tom Brady would lead New England to a Super Bowl title the very next season, and five more between 2003 and 2018.

Jets fans can only wonder what might have been. Belichick will never look back.