The Allegheny County Medical Examiner's Office said Wednesday that Gilliam died Tuesday night at the LA Fitness gym in Bridgeville while he was playing basketball.
The office says a cause of death has not yet been determined pending an autopsy.
Dick Raphael/NBAE/Getty Images
Armen Gilliam, seen in 1989 against the Celtics' Kevin McHale, played 13 seasons in the NBA.
Gilliam, a 6-foot-9 forward, played 13 NBA seasons with six teams after leading UNLV to a 37-2 record and the Final Four in 1987. He was the No. 2 overall pick of the Phoenix Suns in the 1987 NBA draft.
Nicknamed "The Hammer," Gilliam played for the Suns, Charlotte Hornets, Philadelphia 76ers, New Jersey Nets, Milwaukee Bucks and Utah Jazz.
"We are deeply saddened to learn about the loss of Armen Gilliam," said Rod Thorn, president of the 76ers. "He was a hard-working, physical player during his distinguished 13 years in the NBA and we are proud of the contributions he made to the Sixers from 1990 to 1993.
"On behalf of the entire Sixers organization, we send our deepest condolences to the Gilliam family during this very difficult time."
Gilliam, who averaged 13.7 points and 6.9 rebounds during his NBA career, changed the spelling of his first name from Armon to Armen during his professional playing days.
"On behalf of the entire Phoenix Suns family, I'd like to express our sadness at the news of the passing of Armen Gilliam and offer our condolences to his family," Suns president Lon Babby said in a statement.
"Armen will always have a place in Suns history as only the second No. 2 overall pick for the franchise, but the rugged, tough enforcer known as 'The Hammer' on the court will be remembered by his former teammates and our fans for his easy-going nature off the court."
UNLV retired Gilliam's No. 35 jersey in 2007 and inducted him into the school's athletic hall of fame in 2008. He was a consensus second-team All-American and Big West player of the year in 1986-87 as UNLV went 18-0 in conference play and reached the school's second Final Four.
"He was one of the greatest Rebels ever and one of the best players we have ever had," Jerry Tarkanian, his coach at UNLV, said in a statement released by the university. "He was such a great person. Everybody loved him and he loved everybody. He was such a gentle person and such a caring guy. I am all shook up over it. I think the world of him and am just really shocked."
Gilliam coached and played for the Pittsburgh Xplosion in the American Basketball Association in 2005 and 2006. He also coached Division III Penn State-Altoona from 2002 to '05.
"The Runnin' Rebel family lost a true legend," current UNLV coach Dave Rice said. "As great a player as Armen was, he was even a better person."
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