Dallas wants to make a run at a championship with the aging Dirk Nowitzki and Tyson Chandler still playing at high levels. The Mavericks will pair Rondo with explosive guard Monta Ellis in the backcourt.
Dallas will send forward Brandan Wright, guards Jameer Nelson and Jae Crowder, a 2015 first-round pick and a 2016 second-round pick to Boston for Rondo and rookie forward Dwight Powell. There are lottery protections on the 2015 first-round pick headed to Boston, sources said.
Rondo, 28, will be a free agent in July and his agent, Bill Duffy, gave the Mavericks a strong indication that Rondo would be inclined to sign a contract extension to stay with Dallas this summer, sources said.
The Maverics and Celtics had a trade call scheduled with the league office on Thursday night to complete the deal, which includes Boston getting a $13 million trade exception that it has one year to use.
Unless the Mavericks miss the playoffs in 2015, the first-round pick going to Boston will likely come in the 2016 draft. The 2015 first-round pick is protected from picks 1-3 and 15-30. From 2016 to 2020, the pick is protected until No. 7 in the draft, sources said.
The Celtics will release center Vitor Faverani in order to open a roster spot for the deal, sources said,
Boston has three first-round picks in the 2015 NBA draft, and will have a chance to rebuild around rookie guard Marcus Smart and second-year forward Kelly Olynyk. Boston abandoned hope of re-signing Rondo this past summer.
As much as ever in his eight-plus seasons in Boston, the Celtics left strong impressions with rival organizations in recent days that they were prepared to make a deal for Rondo. Boston has been engaged in discussions with several teams, including the Houston Rockets and Los Angeles Lakers, in recent days. As time progressed with the Houston-Boston talks, there was a sense within the Celtics that Houston was simply trying to drive the price up on a deal for the Mavericks, sources said.
Houston has been inclined to sign guard Patrick Beverley to an extension this summer.
As for the Lakers, they would part only with the 2015 first-round pick that it controls from Houston, sources said. The Lakers wanted to include the expiring contract of Steve Nash, who is lost for the season. Those talks never gained great traction, sources said.
Boston has been consistently shopping forward Jeff Green, trying to acquire a package that includes a first-round draft pick, sources said. Boston has been unable to find that in return for Green, but it is expected the Celtics will keep working to find a deal for Green before the February trade deadline.
Rondo has averaged 8.3 points, 10.8 assists and 7.5 rebounds a game this season. After injuries have plagued him in recent seasons, Rondo is still trying to recapture his stature as an All-Star player.