After nine seasons in Boston, during which he revived a storied franchise and steered it to its first NBA championship in 22 years, Doc Rivers is leaving the Celtics to become head coach of the Los Angeles Clippers, league sources tell the Globe.
Rivers, who was the second-longest tenured coach in the NBA behind San Antonio’s Gregg Popovich (17 seasons), was under contract to coach the Celtics for three more seasons, during which he stood to make $21 million.
But in a deal that was agreed upon Sunday night, the Celtics will let Rivers, 51, out of his contract in exchange for a 2015 first-round draft pick.Though Celtics center Kevin Garnett was involved in previous incarnations of this deal, he is not involved in the current package.
The deal still has to be approved by the league, but given that the deal is much simpler than the one these teams had proposed earlier, there is a strong chance it is approved and the deal is completed as early as Monday.
There are reports that the Celtics have scheduled a noon press conference Monday, but nothing has been officially announced.
Rivers has coached the Celtics for nine seasons, including to its 17th championship in 2008.
Talks between the Clippers and Celtics resumed Sunday after reaching a firm standstill late last week.
The Celtics’ asking price for Rivers had all along been a first-round draft pick, and they weren’t budging on that end. The Clippers, however, had at first refused to offer any compensation for Rivers before later offering a second-round pick.
But the Clippers, who have been urged by point guard Chris Paul to come back to the bargaining throughout this process, have changed their offer.
Paul considers Rivers as his top choice to become the Clippers’ next head coach, and the Clippers’ aim to appease him in an effort to re-sign him this summer when Paul becomes an unrestricted free agent.
Rivers had a non-compete clause in the five-year extension he signed with the Celtics in 2011, meaning he couldn’t coach any other team during that time unless they granted permission — which they did, ending days of speculation about whether he’d honor his contract in Boston.
It’s unclear whom the Celtics are targeting as their next coach.
Rivers’s abrupt departure ends his up-and-down run as the 16th coach in Celtics history.
An NBA player for 13 seasons with the Hawks, Clippers, Knicks, and Spurs, Glenn “Doc’’ Rivers received his first coaching opportunity with the Orlando Magic in 1999, but he was fired in 2003, 11 games into his fifth season with them.
The Celtics hired Rivers in April 2004.
“Danny Ainge called me and asked me to coach the Boston Celtics,’’ Rivers said then. “If you like basketball, I don’t know how you could say no to that.’’
In his first season, the Celtics won 45 games and advanced to the postseason. The next two seasons, they won a combined 57 games and didn’t make the playoffs; Rivers’s job status was no doubt in question.
But in July 2007, All-Star center and former NBA MVP Kevin Garnett arrived in a trade with Minnesota. A month earlier, guard Ray Allen had come to Boston in a trade with Seattle. With Allen, Garnett, and Paul Pierce, the Celtics had a new Big Three.
In their first season together, the Celtics went 66-16 and advanced to the NBA Finals, where they dispatched the Lakers in six games to win the franchise’s 17th title.
Rivers’s team reached the Finals once more in 2010, losing to the Lakers in seven games.
Through that success, Rivers had established himself as one of the premier coaches in the league, and he signed a five-year contract extension worth $35 million in 2011. His $7 million-per-year salary was the richest among NBA coaches, ahead of Popovich by $1 million per year.
But after the 2012-13 season, Rivers, as he has in recent years, expressed doubt about returning to the Celtics, saying he needed to “detox’’ and step away from the game before making a decision.
“I’m coming back until I say I’m not,’’ he said.
In recent weeks, though, league sources told the Globe that Rivers was not at all in favor of coaching a rebuilding team, and that he was especially interested in the possibility of winning a championship again, which the Clippers are built to do with Chris Paul and Blake Griffin.
However, the possibility of facing a rebuilding project in Boston during the course of his contract isn’t something that came out of the blue. In fact, when he signed the extension two years ago, Rivers said he would be committed to the idea of coaching a rebuilding team.
“Well, I don’t think anyone’s looking forward to that, but I’m willing to do that,’’ he said then. “I had a group that has been very loyal to me. I think it would have been very easy for me to just run and go somewhere else and chase something else.
“I just don’t think that’s the right thing to do. Coaches talk about loyalty and team, and I just thought it was time to show it.’’
Rivers posted a 416-305 regular-season record as Celtics coach, the third-most wins in franchise history behind Tom Heinsohn (427) and Red Auerbach (795).
In the postseason, Rivers went 106-59, the second-most wins for a Celtics coach behind Auerbach (148).