In sports, the great ones die alone. There are few poetic send-offs with strolls into the sunset.

The end cannot be a fairy tale because the journey requires too much persistence, too much stubbornness. The truest of legends would rather abandon bliss than stay comfortable and fade away.

Acclaimed filmmaker Woody Allen once said, “I am not afraid of death. I just don’t want to be there when it happens.”

Tom Brady doesn’t want to be there, either. Neither did Michael Jordan or Joe Montana or Brett Favre. LeBron James keeps running from new beginning to new beginning as Father Time huffs after him. They all bow to the undisputed GOAT of sports: competitiveness.

Competition reigns, forever. It forces the most stable superstars to be transient.

On Tuesday, it made Brady and the New England Patriots end their own dynasty. History may refer to Derrick Henry and the Tennessee Titans as the ones that finished them, with cornerback Logan Ryan intercepting Brady’s final pass and returning it for a touchdown at the end of a wild card playoff game two months ago. That was when, after years of speculation, finality reached the doorstep.

But for as done as Brady and the Patriots seemed, they were still a 12-4 team last season that won 10 of their first 11 games. They needed change and youth, but their hopes for a seventh championship weren’t dead.

They were teetering, though, and every year they stayed in the present they complicated their future. Still, given their dominance as well as cyclical nature of sports, how could the future possibly be better, or even close, to the present?

Nevertheless, they waved the towel.

As free agency began, the Patriots weren’t snuggling next to Brady, and teams such as the Los Angeles Chargers and Tampa Bay Buccaneers were giddy about trying to acquire the 42-year-old quarterback. So Brady took to social media Tuesday and sent an Instagram goodbye to the only team he has known in his 20 NFL seasons.

“I couldn’t be the man I am today without the relationships you have allowed me to build with you,” he wrote in thanking the Patriots organization. “I have benefited from all you have given me. I cherished every opportunity I had to be a part of our team, and I love you all for that. Our team has always set a great standard in pro sports and I know it will continue to do just that.”

In the end, a move that had been telegraphed for a year still felt stunning. For two decades, Brady and the Patriots defied logic in creating the longest and most controversial dynasty in American professional sports history. Their accomplishments during this era are still too vast to fully appreciate: six titles, nine Super Bowl appearances, 13 AFC championship game appearances, 18 playoff appearances, 19 seasons of at least 10 wins, 20 straight winning seasons.

Factor in the degree of difficulty in an NFL legislated for parity, and New England can stake its claim as the greatest dynasty in sports, despite the Spygate, Deflate-gate or any other cheater debates. With the strict, indefatigable and brilliant Bill Belichick coaching them, the Patriots staved off the end for so long that, even while anticipating their demise, you wondered if they might find a way to squeeze another three years out of this run.

They didn’t want to take that chance, however. So you’re left with a conclusion that illustrates the very thing that turned the seemingly motley mix of Brady, Belichick and owner Robert Kraft into a dynastic trio: They’re too enamored with the pursuit of excellence to sit together, relax and watch a dynasty die. They’re too competitive to let that happen, particularly Brady and Belichick.

Belichick feared staying the same and getting progressively worse. His interpretation of the Patriots’ way is unforgiving and unemotional: He never holds on to the past, and he refuses to fall in love with the present.

He won Super Bowls and worried about the long playoff run hindering preparations for the next season. He is a machine, a relentless tactician, and in Brady, he found a quarterback with the talent, the mind and the drive to lead a team that transformed all of his coaching philosophies and strategies into an undeviating operation.

This wasn’t going to end with Brady and Belichick playing bridge in some kind of NFL retirement home. Belichick is too callous a team builder. And Brady, for all the monetary sacrifices he has made and all the patience he has shown in declining to demand better offensive talent around him, is too proud to squat on a franchise lukewarm about what he can offer as his 43rd birthday approaches in August.

So TB12 is gone.

“Although my football journey will take place elsewhere, I appreciate everything that we have achieved and am grateful for our incredible TEAM accomplishments,” he wrote.

Brady is making a classy exit, but it’s still difficult and loaded with conflict. He would rather play against his coach than live in doubt with him.

Unlike Montana’s trade from San Francisco to Kansas City, Favre’s exit from Green Bay to Minnesota or Peyton Manning’s departure from Indianapolis to Denver, there is no Steve Young, Aaron Rodgers or Andrew Luck in place to succeed Brady in New England. The Patriots would prefer to welcome uncertainty than let it ride with a future Hall of Famer who, while in decline, can still reflect the talent around him and boost it on occasion.

Age has made Brady human, but he’s still gifted enough to command a top salary. And with his career now year to year, he isn’t into taking pay cuts anymore.

The Patriots weren’t keen on offering a $30 million-per-season contract to a player who can be a star but not their savior anymore. In their cold, value-based model of roster management, it doesn’t compute. Belichick is more terrified of making an exception than revising the franchise as we know it.

The dynasty is over. Even though he never won big as a head coach before Brady, Belichick will continue to be successful. Depending on whom they chose as a new quarterback, the Patriots might even fend off Buffalo and win the AFC East again next season. There still might be time for Belichick, 67, to build a championship roster before he retires. But without Brady, the Patriots will never be the same.

“Tom was not just a player who bought into our program,” Belichick said in a statement. “He was one of its original creators. Tom lived and perpetuated our culture. On a daily basis, he was a tone-setter and a bar-raiser.”

Without the Patriots, Brady figures to finish his career in a similar manner as the franchise he leaves behind: still successful, not the same. He definitely won’t embarrass himself. Depending on the team he chooses, he probably will show there’s more in his tank than imagined.

His career will be defined by those 20 imaginable years in New England, however. There will be much lazy pondering of how his performance with a new team will impact his legacy, as if it’s not secure. But what happens next is merely the ending, not the lasting impression.

The phenomenal career of Tom Brady is left to die alone now. So is the era of Belichick’s incessant genius. Brady and the Patriots had to say goodbye this way, their way, not a forced way.

They weren’t afraid of their dynasty’s death. They just didn’t want to be there when it happened.