LAS VEGAS -- The door to the gym opened on the first day of Team USA's minicamp Tuesday, the players strode inside and Amare Stoudemire was not among them.
The New York Knicks' new forward will not play for the United States in next month's world championships because of problems insuring his contract.
The U.S. team's roster dropped from 22 to 20 as the team spent its first 24 hours together preparing for Turkey, as the Suns' Robin Lopez also pulled out after deciding he was not far enough along in his rehabilitation from a bulging disc in his lower back.
Lopez was a long shot to make the roster, but Stoudemire was expected to be one of the key big men on a roster loaded with talented guards but somewhat thin at the forward and center positions. During the team's first practice Tuesday, David Lee injured his right middle finger and planned to immediately fly back to Oakland to be examined by the Golden State Warriors' medical staff.
The Knicks informed USA Basketball on Monday night that Stoudemire would not be rejoining the team he played for in the 2007 Olympic qualifying tournament. He was left off the roster for the Beijing Olympics but could still play in the 2012 Olympics if the insurance issues are worked out.
Stoudemire's decision "was made for us," team director Jerry Colangelo said. "We don't have to make a decision regarding Amare because if the team who has the investment will not allow him to play because they don't have coverage for him in international play, that eliminates him.
"There's nothing to work out. They said he's out. It sounds like a cliché, but it opens up an opportunity for someone else."
Stoudemire has had microfracture knee surgery, as well as other injuries, a major reason Phoenix wouldn't offer him a maximum-length contract. The Knicks then gave him a five-year deal worth nearly $100 million, even while saying they weren't sure whether the contract could be insured.
According to the Knicks, the insurance policy from Stoudemire's contract with the Suns is still in place, but it excludes his surgically repaired left knee. The Knicks have begun working to secure insurance on his new deal, but that hasn't been completed.
"I understand the New York Knicks' concern, also wanting to make sure I'm totally healthy for next season," Stoudemire said. "I'm looking forward to having a big year with the Knicks organization, so I understand both sides."
Without proper insurance, NBA teams can prevent players from taking part in summer events.
"He had to pull out because he couldn't get insurance on his knees. So, he's not able to play," said Knicks coach Mike D'Antoni, who is an assistant with the U.S. team. "I don't know if his [future USA Basketball] status has changed or not. I have no idea. I hate it for him, but it's business."
With the players who led the Americans to the 2008 Olympics gold medal taking the summer off, USA Basketball was counting on Stoudemire. The world championships begin Aug. 28.
"He's disappointed, we're disappointed, but we have to honor the team's request, decision to pull him. I think it was late notice," Colangelo said. "He had a big year. He's healthy, he was hungry, and so we lose that. But having said that, it opens up another opportunity for another big."
Asked about his commitment to playing in the world championships recently while taking questions from the media on Twitter, Stoudemire wrote: "I'm so ready to play for USA. There isn't anything that would stop me for playing for the US."
Chris Sheridan is a senior NBA writer for ESPN.com. Information from The Associated Press was used in this report.