Sources: Teams agree to Marion deal

The Dallas Mavericks and Toronto Raptors, living up to the wild tenor of the past few weeks in the NBA, have hatched a complicated sign-and-trade arrangement that went through numerous constructions Wednesday before resulting in an agreement in principle that will send Shawn Marion to Dallas and absorb the Raptors' much-anticipated signing of Hedo Turkoglu.

Sources close to the negotiations told ESPN.com on Wednesday night that a trade call has been scheduled with the league office for Thursday, indicating all sides have agreed to the terms of a transaction that, in its final form, will also involve the Memphis Grizzlies and the Orlando Magic.

Sources said the Mavericks, after securing Memphis' participation as a third-team facilitator, contacted numerous teams to expand the deal and believed they were close to securing a fourth trade partner from the Eastern Conference. That team, according to ESPN The Magazine's Ric Bucher, was the Chicago Bulls, who would have sent Tim Thomas to the Mavericks.

But one source close to the process told ESPN.com that the deal was later scaled back to a three-team arrangement without Chicago before it was expanded yet again to fold in the Raptors' signing of Turkoglu.

The deal, according to sources, calls for the Mavericks to acquire Marion and Kris Humphries from Toronto and Greg Buckner from Memphis, with Marion to receive a five-year contract worth an estimated $39 million. Buckner has had two previous stints with the Mavericks but is likely to be released, sources said.

The Grizzlies will land Jerry Stackhouse from Dallas and a substantial cash payment to buy out Stackhouse's contract. Only $2 million of Stackhouse's $7.25 million salary next season is guaranteed, as long as he is waived by Aug. 10.

The Raptors will receive Devean George and Antoine Wright from the Mavericks, while also preserving their $5.9 million midlevel exception for the coming season by turning their acquisition of Turkoglu -- who is getting a five-year deal worth an estimated $53 million -- into a sign-and-trade as opposed to an outright signing. Assembling the trade this way could also enable Toronto to re-sign Carlos Delfino, after it appeared the Raptors would have to renounce Delfino to help make room for the Turkoglu signing.

The Magic, meanwhile, were motivated to join in the trade because their participation, as opposed to merely letting Turkoglu walk, will create a valuable trade exception (worth about $7 million) that they can use in future deals.

The inclusion of Humphries, Wright and George gave the Raptors more financial incentive to help Marion find a new home via sign-and-trade, as both George and Wright are heading into the final year of their contracts but Humphries has two years left on his deal. Toronto, furthermore, is in need of a shooting guard after Anthony Parker signed Wednesday with the Cleveland Cavaliers, so adding Wright gives the Raptors a credible starter until newly drafted DeMar DeRozan is ready to contribute.

The main thrust of Wednesday's complicated maneuvering, though, is Marion's move to Dallas, since Turkoglu's commitment to join the Raptors has been known since the weekend.

The Mavericks are hoping that the combination of Marion and Orlando restricted free agent Marcin Gortat -- along with the re-signing of Jason Kidd -- will greatly improve the depth and flexibility possessed by a team that won 50 games last season and advanced to the second round of the playoffs before losing to Denver. The Magic can match the five-year, $34 million offer sheet Gortat has signed with Dallas but are expected to let him go.

Mavs owner Mark Cuban has said for months that he was prepared to be as aggressive as possible this summer as opposed to waiting for the free-agent bonanza of 2010, when Dallas initially was expected to have substantial cap space. With these moves, Dallas can start Marion at small forward next to Dirk Nowitzki and shift Josh Howard to shooting guard, with Sixth Man Award winner Jason Terry staying in a bench role. The Mavericks also believe they will have a strong small-ball unit when they elect not to play Gortat or Erick Dampier, featuring Howard at small forward, Marion at power forward and Nowitzki at center.

Sources say the Mavericks are determined to keep Howard even with Marion on the way, believing that Howard will have a strong season with free agency looming in the summer of 2010. If there's a concern for Dallas, it's that Marion will be yet another key member of the Mavs' core who is over 30, joining Nowitzki (31), Kidd (36), Jason Terry (31) and Howard (who turns 30 in April).

Marion earned $17.8 million last season and was traded for the second straight February when Miami sent him to Toronto in a swap for Jermaine O'Neal. He went from Phoenix to Miami one year earlier in the Shaquille O'Neal trade.

Yet sources say Toronto was intent on re-signing Marion, having seen late-season signs of promise in his collaboration with Chris Bosh and Andrea Bargnani. But then the Raptors realized they had an 11th-hour shot at convincing Turkoglu to back out of a verbal commitment he had given the Portland Trail Blazers.

A deal with Dallas appeared to be Marion's best and last hope for securing a new contract starting above the $5.9 million midlevel exception, given that the Cavaliers -- despite their recent pursuit of Trevor Ariza and Ron Artest and a well-chronicled need for a combo forward -- were not making a hard push for him.

The Mavericks on Wednesday also signed free-agent swingman Quinton Ross to improve their perimeter defense and replace outgoing Wright. Dallas' moves also would appear to make it unlikely that the team will try to bring back free-agent forward Brandon Bass.

"It's been a long day of looking at spreadsheets, reading NBA cap rules and rubbing my eyes," Cuban said via his Twitter account.

Marc Stein and Chad Ford are senior NBA writers for ESPN.com. ESPN The Magazine's Ric Bucher contributed to this report.