Momentum has been building toward this sort of announcement from a pro athlete in a top league in the United States. NFL players Brendan Ayanbadejo and Chris Kluwe were outspoken in support of state gay-marriage amendments during last year's elections. President Barack Obama spoke about his support for gay marriage during his re-election campaign.
The topic made waves during Super Bowl week when one player, San Francisco 49ers cornerback Chris Culliver, said he wouldn't welcome a gay member of his team. At the time, Ayanbadejo estimated that at least half of the NFL's players would agree with what Culliver said, at least privately.
On Monday, NFL Commissioner Roger Goodell sent a memo to teams reiterating the league's anti-discrimination policy about sexuality. It includes a section on questions teams cannot ask prospective draft picks and free agents. After the NFL combine in February, three players said officials posed questions about sexual orientation.
Earlier this month, the NHL and its players' union partnered with an advocacy organization fighting homophobia in sports, and Commissioner Gary Bettman said the You Can Play Project underlines that "the official policy of the NHL is one of inclusion on the ice, in our locker rooms and in the stands."
"I would say the NHL has been a force to kind of obviously embrace and encourage. ... What (Collins) did, I think it's definitely (good) for basketball, and the same for hockey, too. It's going to be encouraging for more guys to step up and just be open about themselves," Washington Capitals forward Joel Ward said.
Living in the nation's capital last month while the U.S. Supreme Court heard arguments about same-sex marriage had an effect on Collins, who says "the strain of hiding my sexuality became almost unbearable" at that time.
"Less than three miles from my apartment, nine jurists argued about my happiness and my future. Here was my chance to be heard, and I couldn't say a thing," he writes. "I didn't want to answer questions and draw attention to myself."
After being a first-round draft pick in 2001, Collins has averaged 3.6 points and 3.8 rebounds for the New Jersey Nets, Memphis Grizzlies, Minnesota Timberwolves, Atlanta Hawks, Celtics and Wizards.
In his SI piece, he jokes self-effacingly about his journeyman career and a parlor game known as "Three Degrees of Jason Collins."
"If you're in the league, and I haven't been your teammate, I surely have been one of your teammates' teammates. Or one of your teammates' teammates' teammates," he writes.
Never a star, he acknowledges, "I take charges and I foul — that's been my forte. ... I set picks with my 7-foot, 255-pound body to get guys like Jason Kidd, John Wall and Paul Pierce open. I sacrifice myself for other players."
He continues: "I go against the gay stereotype, which is why I think a lot of players will be shocked: That guy is gay? But I've always been an aggressive player, even in high school. Am I so physical to prove that being gay doesn't make you soft? Who knows? That's something for a psychologist to unravel."
As for what response other NBA players will have to his revelation, Collins writes: "The simple answer is, I have no idea."
"Openness may not completely disarm prejudice, but it's a good place to start. It all comes down to education. I'll sit down with any player who's uneasy about my coming out," he says in his account, adding: "Still, if I'm up against an intolerant player, I'll set a pretty hard pick on him. And then move on."
On Monday, there was an outpouring of positive sentiments.
In texts to the AP, Wizards guard Garrett Temple wrote, "I was surprised. I didn't know and I was right next to him in the locker room. It definitely took a lot of courage for him to come out. He was a great teammate," and rookie Bradley Beal said: "I didn't know about it! I don't think anyone did! I am proud of his decision to come out and express the way he feels and I'm supportive of that!!"
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