The Boston Celtics are engaged in discussions on several fronts to trade All-Star guard Rajon Rondo, with the Dallas Mavericks emerging as a motivated suitor, league sources told Yahoo Sports.

Boston has been exchanging proposals with several teams on Rondo, including the Mavericks and Houston Rockets, sources said.

As part of package, the Mavericks are willing to give Boston a 2015 first-round pick with limited lottery protection, sources told Yahoo Sports.

Before a deal is consummated, Dallas needs to confer with Rondo's agent, Bill Duffy, about the franchise's ability to re-sign him as a free agent in the summer. Those conversations wouldn't happen until an agreement is in place.

The Mavericks' interest has grown in the past several days, prompting the organization to begin further fact-finding on Rondo, sources said. The Mavericks are searching for ways to close the gap with the first-place Golden State Warriors, and are weighing a Rondo-Monta Ellis backcourt.

View photos Rajon Rondo, 28, will be a free agent in July. (USAT) More

Celtics general manager Danny Ainge seems determined to mine the best offer out of the market and move Rondo soon, making a full commitment to a rebuild. Boston has two first-round picks still to come from the Brooklyn Nets over the next three years and Ainge will have a chance to completely overhaul his roster.

Trade talks with Rondo have been focused more in the Western Conference than Eastern, sources said.

Boston has been consistently shopping forward Jeff Green, trying to acquire a package that includes a first-round draft pick, sources said. Rondo being available would suggest Ainge is prepared to undergo a deeper rebuilding project and push harder for the highest possible draft position in the 2015 NBA draft.

Rondo, 28, will be a free agent in July, and Boston has been reluctant to meet his hope for a maximum – or near max – contract extension. Boston has been pleased with rookie point guard Marcus Smart, and could decide to turn the team over to him in a post-Rondo era.

Rondo has averaged eight points, 10.6 assists and 7.5 rebounds a game this season.

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