Atlanta Hawks (search) center Jason Collier died early Saturday after he had trouble breathing and was stricken in his home, his father said. He was 28.

General manager Billy Knight said the cause of death was not immediately clear for the 7-foot, 260-pound player. He said Collier had "no issues" in a preseason physical given to all players.

Jeff Collier told The Associated Press his son died in an ambulance on the way to the hospital and did not have any diagnosed health problems apart from his knees.

Team spokesman Arthur Triche initially said Collier possibly died of cardiac arrest (search), but would not provide details. He later said the team was not sure how Collier died.

"We'll wait until the experts can tell us, but there's no comments about any speculating at all that I'm going to do," Knight said. "Right now we just think about Jason and his family, his wife and a daughter. He was a good guy, a great teammate and a member of our organization. We're going to miss him."

The Hawks canceled an open scrimmage Saturday because Knight said the team was devastated. The Hawks play an exhibition game Monday at Charlotte, N.C.

"The players took it hard, as you would expect," Knight told the AP. "We'll try to deal with it and keep moving forward."

Jeff Collier said he received a phone call at 3:30 a.m. Saturday from Jason's wife, Katie, who said her husband was having trouble breathing and quickly turned blue.

"You get a call and it's your daughter-in-law crying saying she's giving him CPR and trying to keep him going," Jeff Collier said. "I guess it took awhile for the paramedics to get there. He had a slight pulse when they took him and he passed away in the ambulance while they took him to the hospital."

Jeff Collier told the AP by phone from his home in Springfield, Ohio, that his son had knee surgery when he played in Houston.

"Now all of a sudden this comes up," he said. "We don't know exactly what happened. I'm anxious to find out. But I guess it doesn't make a whole lot of difference at this point."

Collier was a part-time starting center the last two seasons after playing mostly as a backup in three years at Houston. He began his college career at Indiana before transferring to Georgia Tech (search).

Former Tech coach Bobby Cremins said Collier "was a happy-go-lucky kid."

"He married an Atlanta girl and adopted Atlanta as his hometown," Cremins said. "He came back and got his degree, which I was very proud of."

Tech's director of basketball operations, Willie Reese, an assistant coach in Collier's senior year, said "I would have let Jason watch my kids all day, and I think that says a lot."

"He's the type of guy you wish would play in the NBA for 10 years, because he's a professional and is a good role model," Reese said. "That's the type of person you want in the NBA, and the type of person you want at Georgia Tech."

Collier started 44 games last season for Atlanta, averaging 5.7 points and 2.6 rebounds in 13.5 minutes. With the addition of Zaza Pachulia, Collier was not projected as a starter this season but was viewed as a top backup. In two preseason games, Collier averaged 3.5 points and 3.0 rebounds.

Collier was drafted by Milwaukee in 2000 in the first round, the 15th pick overall, and was traded to Houston.

Jeff Collier said Jason had been married to Katie for four years and they have a 1-year-old daughter, Elezan.

The elder Collier played at Georgia Tech from 1972-76 and said his son initially decided to wear the same No. 52 he did at Tech.

"He was a beautiful kid," Jeff Collier said. "Everybody he touched liked him. He played basketball from the time he was in the fourth grade until now. I don't think the kid was ever in a fight or an altercation."

Funeral arrangements are incomplete but the family plans a private viewing.

"Jason didn't really care to be a spectacle," his father said. "He would have wanted this to be a quiet thing. Instead of people being grim, he wants them laughing."