Jason Collins has made NBA -- and LGBT -- history. The basketball star comes out as gay on the cover of the new issue of Sports Illustrated. "I'm a 34-year-old NBA center," writes the 12-year veteran of the sport, who is currently a free agent. "I didn't set out to be the first openly gay athlete playing in a major American team sport. But since I am, I'm happy to start the conversation."

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Collins explains his decision to come out now. "I started thinking about this in 2011 during the NBA player lockout. I'm a creature of routine. When the regular season ends I immediately dedicate myself to getting game ready for the opener of the next campaign in the fall," says Collins, who has played as a center for the New Jersey Nets, the Minnesota Timberwolves, the Boston Celtics and the Washington Wizards.

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"But the lockout wreaked havoc on my habits and forced me to confront who I really am and what I really want. With the season delayed, I trained and worked out. But I lacked the distraction that basketball had always provided."

The athlete adds that years of secrecy took their toll. "It takes an enormous amount of energy to guard such a big secret. I've endured years of misery and gone to enormous lengths to live a lie. I was certain that my world would fall apart if anyone knew," he writes. "And yet when I acknowledged my sexuality I felt whole for the first time. I still had the same sense of humor, I still had the same mannerisms and my friends still had my back."

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None other than former President Bill Clinton immediately applauded Collins; Clinton's daughter, Chelsea, was pals with Collins when they were both students at Stanford University.

"I have known Jason Collins since he was Chelsea's classmate and friend at Stanford. Jason's announcement today is an important moment for professional sports and in the history of the LGBT community," Clinton says in a statement. "It is also the straightforward statement of a good man who wants no more than what so many of us seek: to be able to be who we are; to do our work; to build families and to contribute to our communities. For so many members of the LGBT community, these simple goals remain elusive. I hope that everyone, particularly Jason's colleagues in the NBA, the media and his many fans extend to him their support and the respect he has earned."

This article originally appeared on Usmagazine.com: Jason Collins, NBA Star: "I'm Gay"