Why do the greatest athletes seem to have the most reluctant retirements?
Remember when ESPN ranked the top 100 athletes of the 20th century?
The No. 35 slot was given to a horse, Secretariat, while Michael Jordan edged out Babe Ruth and Muhammad Ali for No. 1.
The 21st century is already off to a roaring start, with Tom Brady, LeBron James, Serena Williams and many others making strong cases. Sports Century Volume 2 should be fun to watch in 2099.
But will they ever rank the best athletes from two half centuries, 1951-2050, giving Jordan and Brady the chance to compete? And if so, could final chapters be the deciding factor?
Nobody did it quite like Jordan. He retired at 30, gave baseball a shot, then returned to hoops and led the Bulls to three more NBA titles.
After taking three more years off, Jordan didn't embarrass himself during his two-year return with the Washington Wizards. He averaged 20 points and 6 rebounds at 39, but he couldn't lift a flawed Wizards team into the playoffs.
The "Last Dance" documentary seemed to deliver the final word on Jordan's career. In retrospect, he wanted that Bulls team to continue, though that would have been complicated by his cigar-slicing accident, Scottie Pippen hitting free-agency and Tim Floyd being proclaimed coach-in-waiting.
Brady's final chapter couldn't have gone much better. In his first year after leaving coach Bill Belichick and the New England Patriots, Brady led Tampa Bay to a Super Bowl title. The next year, he led the NFL in passing yards at 44, and lost a close game in the playoffs to the eventual Super Bowl champion Rams.
Then he retired. Then changed his mind. Then divorced supermodel Gisele Bündchen after a 13-year marriage.
Assuming this retirement sticks, Brady's final season wasn't great by his standards. But it was still pretty good. He finished third in the league with 4,694 passing yards and made the playoffs. So let's face it, another comeback isn't unreasonable.
Brady's only competition in QB longevity is George Blanda, who threw for just 77 yards during his age 45 season with the Oakland Raiders in 1972.
And this is just a hunch, but sitting out last season probably wouldn't have solved whatever marital issues were brewing between Brady and Bündchen.
When it comes to false retirements, it will be tough for anyone to top quarterback Brett Favre.
After three years of waiting for decisions, the Packers finally gave Favre a deadline in 2008 and he announced his retirement. Then changed his mind and showed up at training camp, even though the team was ready to commit to Aaron Rodgers.
Favre was eventually traded to the Jets, had a disappointing season and was accused of sending inappropriate photos to a team employee. So he retired again, then joined the Vikings and nearly led them to the Super Bowl in 2009. Favre's 20 years in the NFL finally ended on a cold Monday night at TCF Bank Stadium when sacked by the Bears' Corey Wooten.
There are several examples in history of publicity stunt-inspired comebacks. White Sox owner Bill Veeck brought back Minnie Minoso for limited at-bats in 1976 and '80 - and he got a hit at age 52.
Dizzy Dean came back six years after he retired. Bob Cousy returned seven years after retiring from the Celtics, and dished some assists as player-coach of the Cincinnati Royals in 1970.
Legendary pitcher Satchel Paige joined the Kansas City A's 12 years after he retired, and tossed three scoreless innings against the Red Sox at 58. Why he didn't just stay in the rotation remains a mystery.
The most dramatic return from retirement might be Mario Lemieux. After missing three years battling Hodgkin lymphoma and severe back pain, he returned to play five more seasons with the Pittsburgh Penguins.
Tennis player Justine Henin retired in 2008 while ranked No. 1, citing injuries. She returned about two years later, but wasn't the same.
Boxers have a long history of false retirements, but George Foreman's path stands out. After sitting out for 10 years, he returned to the ring and was competitive for 10 years before pivoting to the in-home grilling business.
So whatever big-time athlete is next to announce retirement, we should know to take it with a grain of salt and expect revisions. All eyes are on you, Aaron Rodgers.
Twitter: @McGrawDHSports