NBA veteran Jason Collins became the first active male player in the four major American professional sports to come out as gay.

Jason Collins on the cover of Sports Illustrated (SI)

The 34-year-old center, who has played for six teams in 12 seasons, wrote a first-person account posted on Sports Illustrated's website Monday. Collins finished this past season with the Washington Wizards and is now a free agent. He says he wants to keep playing.

"If I had my way, someone else would have already done this," he writes. "Nobody has, which is why I'm raising my hand."

Collins played in a Final Four for Stanford and reached two NBA Finals. His twin brother, Jarron, was also a longtime NBA center. Jason says he came out to his brother last summer.

White House spokesman Jay Carney called that decision courageous and says the White House supports Collins. He says he hopes the 34-year-old center's NBA colleagues will also offer support.

"We view that as another example of the progress that has been made and the evolution that has been taking place in this country," Carney said.

NBA Commissioner David Stern said in a statement: "Jason has been a widely respected player and teammate throughout his career and we are proud he has assumed the leadership mantle on this very important issue."

Among those offering support on social media was former first daughter Chelsea Clinton, a friend from Stanford. She tweeted: "Very proud of my friend Jason Collins for having the strength & courage to be the first openly gay player in the NBA."

Mostly a backup in his career, Collins has averaged 3.6 points and 3.8 rebounds for the Nets, Grizzlies, Timberwolves, Hawks, Celtics and Wizards. He was traded from Boston to Washington in February. Collins was the 18th pick in the first round of the 2001 NBA draft.

Several male athletes have previously come out after they retired, including the NBA's John Amaechi, the NFL's Esera Tuaolo and Major League Baseball's Billy Bean. But Collins is the first to do so while planning to continue playing.

(Copyright 2013 The Associated Press. All Rights Reserved)