A Celtics spokesperson confirmed Thomas made the request, which the team will honor. Thomas, who will make his Cavaliers debut Tuesday against the Portland Trail Blazers, will not play against the Celtics on the second night of a back-to-back.
Thomas explained the decision while responding to a critic on Twitter:
The spokesperson said the Celtics plan to honor Thomas at a later date.
Thomas, 28, spent two-plus seasons with the Celtics. He emerged as one of the NBA's premier point guards during his short stint, highlighted by a 2016-17 campaign that saw him make his first All-NBA team and lead the Celtics to the East's No. 1 seed.
Boston traded him along with Jae Crowder, Ante Zizic and two draft picks to the Cavaliers for Kyrie Irving this offseason. The move was seen by some—including Thomas—as disheartening given the quick bond he developed with the city. Celtics fans were in particular ingratiated to Thomas after he played in the 2017 playoffs following the tragic death of his sister.
"Boston is going to be all love," Thomas told Lee Jenkins of Sports Illustrated. "I might not ever talk to [Celtics' general manager Danny Ainge] again. That might not happen. I'll talk to everybody else. But what he did, knowing everything I went through, you don't do that, bro. That's not right. I'm not saying eff you. But every team in this situation comes out a year or two later and says, 'We made a mistake.' That's what they'll say, too."
Thomas has missed the first 36 games of the season while recovering from a torn labrum in his hip. He's expected to have a minutes limit, though the full plan for his return has yet to be determined.