Isaiah Thomas discusses his feelings after being traded by the Celtics and how he doesn't hold any grudges despite what could have been. (0:35)

BOSTON -- This was the moment Isaiah Thomas had always dreamed of.

For years, the diminutive guard bounced from team to team, constantly seeking two things: respect and a place to call home. Here, playing for the Boston Celtics, Thomas had found both.

However, he has failed to recapture either of them since the Celtics traded him away in 2017. And, as Thomas slowly walked from the visitors' tunnel to the Denver Nuggets' bench at the 7:06 mark of the first quarter of Monday night's game at TD Garden while a tribute video celebrating his two-plus seasons with Boston played on the Jumbotron above him, that fact seemed to hit him all at once.

"I was emotional," Thomas would say later. "I almost cried."

When the video ended, Thomas saluted the crowd -- first by flashing a peace sign, then by tapping his left wrist twice, signaling it was, for one final time here, "IT Time" -- as the standing ovation for him, and his accomplishments in Boston, lasted for more than a minute.

"It was special," Thomas would say later.

"That was everything. I appreciate them for doing that.

"That means a lot."

It was a reminder of how special his run here was, as was his connection with these fans. It also was a reminder of just how far away from that player he is today.

Time catches up to everyone eventually on a basketball court. Some athletes -- quarterbacks, pitchers, golfers are all examples -- can at least temporarily overcome age by sheer skill. In those instances, the brain can make up for what the body lacks.

Basketball, however, is not one of those sports. Sure, some of the greats have managed to endure into their late 30s. But most of those players -- Tim Duncan and Karl Malone, for example -- have the one other thing that doesn't change with age: size. Whether someone is 20 or 40, they remain 7 feet tall.

Or, in the case of Isaiah Thomas, they remain 5-foot-9. (Maybe.)

Isaiah Thomas looks on at his tribute video at TD Garden on Monday night. Maddie Meyer/Getty Images

That being said, even in the NBA, in which eras in the sport shift every three to five years -- and always come and go faster than anyone expects -- the reign of the "King of the Fourth" remains singularly stunning in how short it truly was.

For two seasons, Thomas shone as one of the NBA's brightest stars for one of its most storied franchises. It was the perfect marriage of person and opportunity on both sides. The Celtics had a team full of hard-working role players and needed a scorer to serve as its anchor on offense, a role Thomas played superbly. Along the way, he became the latest in a long line of underdog stories to enthrall the patrons of this city's sports teams.

That was true for the way he defied the odds in putting up ridiculous stat lines while almost always being the smallest player on the court. It also was true for the way he stood tall in the face of the most overwhelming adversity: both the tragic death of his sister, Chyna, in a car crash during the 2017 playoffs, and his playing through -- and eventually being sidelined by -- a hip injury.

"I went through a real life situation here when I lost my sister that this whole city and organization went through with me," Thomas said. "And I think that's why, other than ... the love is always there, but that's what took it to another level.

"I went through the worst situation you can possibly go through in life with these people, and they was right there with me. Everybody in the city, the organization, they was right there with me, they went through that with me. That's why Boston means so much to me."

Then, as quickly as he arrived as a star, and was embraced as one of this city's favorite sons, he was gone. Thomas was sent to the Cleveland Cavaliers in a package for Kyrie Irving that -- despite the protestations of Anthony Davis Sr. several weeks ago -- was always, and will remain, the only move the Celtics could have made.

The version of Thomas that took the court with 2:42 to go in the first quarter Monday night was a far cry from the one who captivated this crowd so many times in his short stint in Boston. The hip issues that caused him to miss the final three games of the 2017 Eastern Conference finals have, at least for now, transformed Thomas from an efficient scoring machine into a liability at both ends.

That was exemplified in his 6-minute, 50-second stint in Monday's first half. When he entered the game, the Nuggets led by four. By the time he exited with 7:52 remaining in the second, the Nuggets trailed by four. Thomas missed both of his shots -- a short runner in the lane, and an open 3-pointer on the right wing -- and committed a turnover, to go along with two assists.

With Thomas on the bench for those same minutes in the second half, Denver put the game away -- eventually winning 114-105 and, in the process, clinching the franchise's first playoff berth in six seasons.

Isaiah Thomas' past four seasons Isaiah Thomas was an All-Star in his two full seasons in Boston, but his two seasons since being traded have been marred by injuries and poor production. 2015-17 2017-19 Games 158 42 PPG 25.5 13.4 FG Pct 44.6 37.1 3-Pt FG Pct 37.7 28.8 APG 6.1 4.0

Thomas' numbers in limited action this season aren't any prettier. He's averaging 7.7 points per game on 36.4 percent shooting from the floor, including 26.5 percent from 3-point range. Denver, meanwhile, has been outscored by 27 points in the 147 minutes Thomas has played this season, and is 12.3 points per 100 possessions worse when Thomas is on the court (minus-7.6) than when he's on the bench (plus-5.3).

All of those reasons are why, earlier this month, Nuggets coach Mike Malone went to Thomas and told him that, after playing nine games since finally returning from hip surgery last month, he would no longer be part of Denver's rotation.

"The reason for me taking him out of the rotation, and our team [struggling] ... our team didn't struggle because of Isaiah Thomas," Malone said before Monday's game. "That was an unfair kind of assessment going around. 'We're struggling because of Isaiah.'

"No, we were struggling because 'we' were struggling. It's never about any individual."

Sometimes, though, it is. Professional sports are big business. Very rarely, if ever, does a feel-good story have a happy ending. Thomas' time in Boston is proof positive of that fact. How could someone so universally beloved here be sent packing?

Because it was the right business decision. Irving simply is a much better player -- especially when compared to this version. And it isn't looking like the old version is coming back anytime soon -- if ever.

"I'm not sure," Malone said, when that very question was posed to him. "What I will say is this: If anybody can do it, it's him. His heart, his determination, his confidence.

"[But] will he be the player from two years ago, that led the league in fourth-quarter scoring, and averaged 29 per game and was an All-Star? I don't know."

Neither can anyone else. The evidence, though, suggests he won't.

It's all unfortunate for Thomas, who was on a well-below-market contract while he was starring with the Celtics -- only for his hip to give out before he could be paid commensurate with his performance in Boston.

Sports aren't fair. Injuries happen. Opportunities come and go. Thomas, who was the 60th and final pick in the 2011 draft out of Washington, has experienced that at every step of the way. He has managed to overcome it thanks to a combination of supreme confidence and a singular skill set.

The confidence still remains.

"I just want a legit opportunity," Thomas said. "Whatever the role may be, it's going to be. But I know I can play at a high level again. And if given the opportunity, I can be an All-Star, I can be All-NBA, I can be all that, because I physically feel great.

"But it's all about the opportunity. If I get an opportunity, I'm going to be ready for it. I'm going to take full advantage of it. And when this summer comes, I'm going to just figure out what's the best opportunity, what's the best situation for myself and my family, and then go from there."

Thomas conspicuously wore green-and-gold Nikes during Monday night's game. He was asked about them afterward.

"You know what's crazy? Those green-and-gold sneakers were for the Finals the last year I was here," Thomas said. "So I always kept those. I got a couple other pairs, too, but those were made for the NBA Finals.

"And then we lost to the Cavs, and things like that."

Those other "things" included Thomas being traded away, and his career being sent careening in a far different direction than he ever imagined. It's one that, on this night, left him in a reflective mood, as he had to grapple with just how far his star has fallen from its apex here.

"It was special here, but I didn't understand that until I wasn't here anymore," Thomas said. "I was so locked in in those moments that I didn't really know what was happening.

"So there were times after I got traded where I sat back and really thought about things that I did as an individual, the things that we had done as a team, and those were amazing moments that I will cherish for the rest of my life.

"Like, those moments were everything, and we did some legendary s---."

Then, Thomas paused.

"I did some legendary s---, too."

For a moment in time, Boston gave Thomas everything he ever wanted. Monday night reminded everyone, including Thomas, of that.

It also reminded everyone that those days are over.