Cavs general manager Koby Altman confirmed the agreement to the Akron Beacon Journal.
The third-leading scorer in the National Basketball Association (NBA) regular season last term (28.9 points per game) behind Russell Westbrook and James Harden, Thomas suffered a hip injury that ultimately forced him out of May's Eastern Conference Finals.
The Cavs had initially sought an additional first-round pick or another young player as insurance against Thomas's injury, a negotiating gambit rejected by Boston. Wojnarowski suggested the Cavs could void the trade after Thomas flew to Cleveland Friday for his medical workup.
The Cavaliers had until 10 a.m. Thursday morning to void the deal based upon Thomas' physical which was conducted last Saturday.
The C's threw in Miami's 2020 second-round pick to finalize the deal bringing Kyrie Irving to Boston, and the nation is left wondering why the deal was held up for so long over such a small piece.
And while Irving said he hasn't put much thought into all that will go into facing his now-former team, he won't have to wait long to do just that; the Cavs and Celtics will kickoff the NBA's 2017-18 campaign with an October 17 date in Cleveland.More news: Iran voices concerns over Rohingya muslims in Myanmar
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"There's never been an indication that I wouldn't be back, and there's never been an indication that this is something messing up my career", Thomas told ESPN on Tuesday. From the start the Celtics front office said it was up front with everything they knew about IT's hip and recovery, so even if Cleveland's doctors saw things differently why should Boston pay more?
Thomas opted to not have surgery and is undergoing a rehab process instead this offseason.
Watch Irving break it all down in this clip from the introductory press conference, which also featured forward Gordon Hayward, who joined the Celtics as a free agent this off-season.
Irving admitted he hasn't talked to LeBron James since the trade machinations began. "It's a real slow rehab process, but it's getting better and that's what it's all about", Thomas told The Boston Herald.
The Cavs drafted Irving with the No. 1 overall pick in 2011. "The Celtics believe they were fully forthcoming in detailing Thomas' injury, sources said".