After the Portland Trail Blazers chose to use their amnesty clause to clear the contract of All-Star Brandon Roy from the salary cap Thursday, his agent wanted something made clear: Roy is retiring forever from the NBA.

Doctors have told Roy that his degenerative knees make it impossible for him to continue playing in the NBA. He has no more cartilage in his knees, and the continued grind of playing in the league could ultimately jeopardize his ability to walk.

[ Related: Agent: Baron Davis has back injury ]

“Brandon has no intention of returning to professional basketball,” his agent, Greg Lawrence, told Yahoo! Sports. “He has been instructed by several doctors that he has a career-ending injury and needs to stop playing immediately. He has chronic problems in both knees and his long-term health is already in jeopardy. …Playing further will unquestionably have serious consequences.

“Brandon appreciates the support of the Blazers organization and fans, and is glad they will be able to

The Orlando Magic have informed teams that they're ending trade talks for Dwight Howard and plan to start the season with the All-Star center on their roster, league sources told Yahoo! Sports.

The Magic's decision came Wednesday after the Nets assembled a multiteam trade proposal for Howard that would have sent the Magic center Brook Lopez, Portland Trail Blazers forward Gerald Wallace, point guard Jordan Farmar and a first-round draft pick. The Nets also would have taken on Chris Duhon and Hedo Turkoglu. The Blazers would have received four draft picks for Wallace.

With the framework of a deal in place, talks had reached the ownership level in Orlando, league sources said. Nevertheless, Magic ownership did not approve of the trade, and general manager Otis Smith then informed teams Howard had been removed from the market.

Howard told teammates on Tuesday that he thought the trade to the Nets was a "done deal," a league source told Y! Sports. Twenty-four hours later on Wednesday,

Talks between the Orlando Magic and New Jersey Nets for a Dwight Howard blockbuster trade have gathered momentum over the past several days, and the framework of a possible four-team deal has taken shape, league sources told Yahoo! Sports.

Front office sources say Nets general manager Billy King has aggressively pursued the necessary players and picks to try and satisfy Orlando's demands for Howard, one of the league’s most dominating and popular players.

The biggest hurdle for the Nets to acquire Howard will still ultimately be the Magic’s willingness to give up their future with him and concede that re-signing him is a lost cause. Orlando could also decide to keep Howard until the trade deadline in March and re-evaluate the market for him. There’s still a belief within the Magic a successful season could help them keep Howard for the long-term.

No deal was imminent, but several league sources said talks were entering a crucial time, and the Nets were trying to get the proposal's

As free-agent forward David West and the Boston Celtics work to complete a difficult sign-and-trade deal, the Indiana Pacers have positioned themselves to sign the power forward should talks with the Celtics flatline on Sunday, league sources told Yahoo! Sports.

The Celtics have been discussing a four-year deal with West, sources said. Still, Boston is limited under sign-and-trade rules with how high it can go with an offer. The Celtics can offer the first three years in the $24 million to $25 million range, but the fourth year would likely not be fully guaranteed.

Several sources believed there would be a resolution Sunday.

Indiana has been discussing a two-year deal with West but with a higher annual salary, sources said. The Pacers have cap space to sign West outright, while Boston, which is over the salary cap, needs the sign-and-trade scenario to acquire him. With the Chris Paul-to-the-Lakers deal falling apart again late Saturday night, the Hornets still hadn't made any calls to

After failing to satisfy trade proposal mandates for the NBA-owned New Orleans Hornets, the Los Angeles Lakers ended trade talks for Chris Paul on Saturday night, league sources told Yahoo! Sports.

As the Lakers changed course, they traded Lamar Odom to the Dallas Mavericks into a trade exception and set course in pursuit of Orlando Magic center Dwight Howard.

The Los Angeles Clippers and Golden State Warriors are expected to return to talks with the Hornets about a Paul deal, front office executives said.

The NBA has taken complete control of the Hornets front office and left general manager Dell Demps and coach Monty Williams without a deal that they wanted to make for Paul. The Hornets have been left in an impossible predicament by commissioner David Stern, who has positioned himself as basketball czar of the Hornets.

In his desire to keep the All-Star point guard on the roster to maximize the league's selling price of the team to potential owners, Stern has shot down two deals to

Orlando Magic superstar Dwight Howard has requested a trade to the New Jersey Nets, league sources told Yahoo! Sports on Saturday.

Orlando GM Otis Smith has made it clear that he will trade Howard wherever the Magic get the best possible package, but the fact that Howard is willing to sign a five-year, $109 million extension with New Jersey makes it likely that the Nets can be the most aggressive in offering an attractive package. New Jersey has been pursuing possible third-team partners to strengthen the offer for Howard, front-office sources tell Y! Sports.

Smith confirmed to the Orlando Sentinel that Howard asked to be traded.

Los Angeles had long been a preferred choice of Howard's, but sources say that several factors have pushed him toward the Nets over the Lakers. Howard has a strong relationship with Deron Williams, and has also resisted following the same career path as Shaquille O'Neal, who left the Magic for the Lakers two decades ago.

The Nets are offering a package

As Chauncey Billups prepares to have his name entered into the NBA's amnesty waiver wire, he has a message for teams considering putting in a bid to secure him for the rest of the season: You'll regret it.

He wants the freedom of free agency to choose a contender, Billups says. As one of the game's great leaders, and gentlemen, Billups warns that player will be a distant memory should a team claim him off the amnesty waiver wire.

"I'm tired of being the glue guy," Billups told Yahoo! Sports by phone on Saturday afternoon. "I'm tired of being viewed as the good guy. After a while, you just kind of get taken advantage of in these situations. I've been known as a leader, and I am a leader, but a leader can be as disruptive as he can be productive, especially when you carry a strong voice and people rally around you. This is about me now. This is about me, and teams should know that right now."

The Knicks picked up Billups' $14.2 million option for the 2011-'12 season, but used the new

The New Orleans Hornets have delivered a reconstructed framework of the three-team blockbuster trade sending Chris Paul trade to the Los Angeles Lakers into the NBA office for approval, league sources told Yahoo! Sports.

In the latest details available to Yahoo! Sports, sources say that New Orleans could send the Lakers Paul, and possibly two Hornets free agents – center Jason Smith and Marcus Banks – would be sent to the Lakers in sign-and-trade agreements.

The Rockets would send Kevin Martin, Luis Scola, a 2012 first-round pick and possibly young players or additional picks to the Hornets.

The Lakers would send Lamar Odom to the Hornets, Pau Gasol to the Rockets and league sources say that Los Angeles was pursuing a first-round pick to send to the Hornets.

"It’s in David Stern’s hands now," one source said. "He’ll decide on the trade."

The NBA was clearly dictating terms of a possible trade of Paul to the Lakers, sources said. The league office is running the Hornets, while they wait