"I came into the league very graciously and want to go out very graciously," the 38-year-old O'Neal told the Associated Press. "My main thought was I would like to play for a winning franchise, somebody that's used to winning, somebody that keeps winning."
With a no-doubt Hall-of-Fame resume and set to be the oldest player in the league, it was not about money. Unlike Karl Malone, this wasn't a last-ditch title grab for a player worried about a legacy of losing. O'Neal sought a tradition of success and the chance to close out his career on a championship note.
His decision follows a long history of legends who gave it one last try in Boston. The dynasty of Celtic Pride formed in the 1950s and 1960s created an atmosphere of success irresistible for aging stars looking to solidify their legacy.
Some -- like Kevin Garnett or Bailey Howell -- arrived with plenty left in the tank. Other fading stars -- like Clyde Lovellette and Arnie Risen -- were brought in by Red Auerbach to play a reduced role and stuck around for multiple years.
However, Shaq seems to belong to a third group of aging legends: Players keenly aware the end is right around the corner and ready to make Boston a brief, final attempt to go out a winner.
How will Shaq be remembered in Boston? Ultimately, that comes down to whether he helps hang a banner in the rafters. Without that title, he'll likely fall into the category of forgotten Celtics. Consider the cases of four legends who preceded O'Neal in Boston:
Artis Gilmore -- 1987-88
The signing of a mammoth 38-year-old center is not unprecedented in Celtics history. Released by the Bulls on Christmas Eve 1987, Artis Gilmore had no shortage of suitors despite his age. A six-time NBA All-Star standing 7-foot-2 generally does not fall into a team's lap in the middle of the season.
As it happened, the Celtics had been trying to plug a hole behind Robert Parish for much of the preceding 18 months. Bill Walton, who filled the role to perfection in the 1985-86 championship season, was still attempting an ultimately unsuccessful comeback. In his absence, Greg Kite filled in behind the Chief, but he had strained his back. Gilmore, still seeking his first NBA title, jumped at the chance to join the top team in the Eastern Conference.
Little was expected of Gilmore besides minutes, and that's essentially all he provided. Averaging a shade over 11 minutes, he helped reduce Parish's workload. Gilmore averaged 3.5 points and 3.1 rebounds in his 47-game stint with the Celtics.
However, a loss to the Pistons in the Eastern Conference finals meant the legendary big man would never hoist the trophy. Ironically, Parish hurt his knee in the decisive game, forcing an overmatched Gilmore into a greater role.
In the offseason, he decided to finish his basketball career in Italy.
Despite being one of five players in history with 20,000 points and 15,000 rebounds, Gilmore isn't in the Hall of Fame. One has to wonder how much his resume would have benefited from a 1988 NBA title.
Bill Walton -- 1985-86
It was one of those trade rumors that just wouldn't die, and this was before the explosion of sports media. In fact, it took an entire summer to get the deal done.
In June 1985, Boston appeared close to acquiring Walton in exchange for Cedric Maxwell, but the Los Angeles Clippers became wary of Maxwell's surgically repaired knee. Come July, talks heated up again when the Clippers reexamined the Celtics forward, who was coming off a lackluster postseason. By early August the deal seemed dead, but an agreement was reached at the end of the month. Finally, on Sept. 6, the swap became a reality with the Celtics adding a future first-round pick that turned into Arvydas Sabonis.
"Basketball, to me, is playing to win the championship," said Walton, who hadn't appeared in the playoffs in seven years.
Walton, 32 but with a body that seemed twice that age, would finally get a crack at another title.
Unlike the other aging legends to join the Celtics, Walton -- like O'Neal now -- had already tasted a title, with the Trail Blazers in 1977. His quest was for a return to glory.
Walton was everything the Celtics had hoped for that season. Staying healthy, he played 80 games, 13 more than he'd managed in any other season. Averaging 7.6 points and 6.8 rebounds in just under 20 minutes per game, Walton took home the Sixth Man of the Year award.
Unlike Pete Maravich before him or Gilmore two years later, Walton got his wish of a championship with the Celtics, who clinched it against the Rockets in six games.
"It's an unbelievable feeling when you have a dream, and the dream comes true -- to be a Celtic and win a championship," Walton told the San Francisco Chronicle. "And I can sit back now and put my feet up."
As is often the case, Walton channeled the Grateful Dead to describe just how he felt.
"There's nothing left to do but smile, smile, smile."
Sadly, the title to that track would've been equally fitting: "He's Gone." Walton's career would consist of only 10 more regular-season games despite multiple comeback attempts.
His renaissance short-lived, Walton is still smiling about that 1985-86 Celtics team.
Pete Maravich -- 1979-80
A member of the Jazz since the franchise's inception in 1975, the move from New Orleans to Utah was not a smooth one for Maravich. The Jazz started the 1979-80 season with losses in 19 of 21 games. New coach Tom Nissalke then opted for a youth movement, meaning Maravich took a seat on the bench -- staying there for 28 games. In January, the Jazz bought out the final 2½ years of his contract.
All signs pointed to Pistol Pete returning to his home state to play for the 76ers, and he even passed a physical in Philadelphia shortly after getting cut loose. However, the lure of a title led him to the "tradition" in Boston.
"I've always wanted to be a Celtic." Maravich said upon signing, according to the New York Times. "I think it's justified because they have 13 championship flags hanging out there. The only flag I have is a little American flag at my house."
Just three months before, the idea of joining the Celtics for a title run would have seemed laughable. Boston finished with the second-worst record in the NBA in 1978-79, but the addition of a young rookie named Larry Bird made the Celtics immediate contenders.
Maravich hadn't sniffed the playoffs in his last six seasons and looked to Boston for his first ring. The leading scorer in NCAA history, he was clearly obsessed with a perceived legacy of losing.
"If I'd have come out with Boston or New York, my whole career, my whole life, would have been changed," Maravich told the New York Times later that season. "I would have been 'Pete Maravich, winner' -- as society puts it -- not 'Pete Maravich, loser.'"
At 32 years old with a pair of creaky knees, Maravich was merely expected to add backcourt depth and scoring. A title in 1980 would have footnoted his career, rather than writing a new chapter. But it also would have ended an association with losing.
After needing two weeks to get back into playing shape, he contributed sparingly until an injury to Chris Ford pushed him into the starting lineup. In 26 games, he averaged 11.5 points as the Celtics completed the biggest win improvement in NBA history.
But in an ending fitting to a tragic figure, the Celtics would be ousted in the Eastern Conference finals by the 76ers, the team Maravich spurned in favor of Boston. Pistol Pete was just 2-for-8 from the field in what would be his final NBA game.
The following September, Maravich opted to retire, having never attained his dream of an NBA championship. Less than a year later, the Celtics captured their 14th title.
Dave Bing -- 1977-78
On Sept. 26, 1977, Bing, soon to turn 34, retired as an NBA player. On his way to the Hall of Fame, he was 14th on the all-time scoring list and sixth in assists.
But one thing eluded him over the course of an 11-year career: An NBA title. So when Auerbach called on Sept. 27, Bing listened.
"He made me an offer I couldn't refuse," Bing said.
His retirement lasted all of 48 hours before Bing decided to take one last crack at a ring. After all, the Celtics had made the playoffs in six straight seasons, taking home two of the last four championships.
Bing would not get his ring. In fact, he wouldn't come close. The Celtics finished 32-50, their worst record since 1949-50.
Seemingly nothing went right. Tom Heinsohn was replaced as coach after 34 games. Jo Jo White battled foot problems that limited him to 46 games. John Havlicek announced his intention to retire at the end of the season. Just after Christmas, Charlie Scott was shipped to the Lakers for a suspended Kermit Washington.
Though Bing had a solid season, averaging 13.6 points, he again retired following the season. This time it was for good. Though still without a ring, he decided to hang it up rather than endure the rebuilding process. Perhaps he was saving his patience for his current job: Mayor of Detroit.
Jeremy Lundblad is a researcher with ESPN Stats & Information. He provides statistical analysis for ESPNBoston.com.