Collins revealed he was gay on Monday in a Sports Illustrated article, a reluctant pioneer who broke one of the last barriers of American sport.
He was given the presidential seal of approval when Barack Obama personally called to congratulate him, and also received overwhelming support from other professional athletes and celebrities from the entertainment world.
Appearing on a popular breakfast television show on Tuesday, Collins looked and sounded like a man at ease with himself.
"I know that I, right now, am the happiest that I've ever been in my life," he told Good Morning America.
"A huge weight has been lifted. I've already been out to my family and my friends, but just to, you know, sort of rip the Band-Aid off and come out on my own terms."
Not everyone was applauding Collins, a center who played last season with the Boston Celtics and the Washington Wizards.
While most comments seemed positive, there were also critics.
Hines Ward, a former wide receiver in the NFL, said the sport would not embrace homosexuality.
"I don't think football is ready," said Hines, now a television analyst with NBC. "There are too many guys in the locker room and, you know, guys play around too much."
Ward was not the first, nor likely the last, from the testosterone-fuelled and violent world of American football to express public discomfort.
Sportswriter Chris Broussard, speaking on ESPN television, grouped homosexual acts with adultery and premarital sex, saying he believed this was "walking in open rebellion to God."
Other commentators suggested that Collins's move was easier because he is not a star and not in his prime. A 34-year-old veteran who has played for six different teams in his 12-year NBA career, Collins is a free agent looking for a new team.
His announcement came at a time of shifting attitudes toward gay rights in the United States, where polls show public opinion is fast moving toward greater acceptance, although a core of social conservatives oppose such change.
In the coming months, the Supreme Court will rule on whether to strike down parts of a federal law that defines marriage as the union between a man and a woman. In 2011, the military repealed a ban on openly gay soldiers.
While Collins is the first active player in the four major men's sports, comprising the NBA, NFL, NHL and MLB, no one thinks he is the last. The other major sports leagues were making preparations for one of their own to come out.
The NFL has been under fire for its perceived homophobic culture but has been busy scrambling to make up ground.
In the days leading up to this year's Super Bowl in New Orleans, San Francisco 49ers cornerback Chris Culliver told reporters he would not welcome a gay team-mate into the locker room.
He retracted his comments but a few weeks later, at least three college football players said they had been asked about their sexual orientation during NFL recruitment interviews, sparking calls for the NFL to do more to fight discrimination.
On Monday, just hours before Collins' admission he was gay became headline news, the NFL - America's most popular sport, with $9 billion a year in revenue - released a 'workplace conduct statement' regarding sexual orientation.
"The NFL has a long history of valuing diversity and inclusion. Discrimination and harassment based on sexual orientation is not consistent with our values and is unacceptable in the National Football League," league commissioner Roger Goodell said.
In the NHL, another rough and rugged league, officials said they had been preparing for years for the arrival of their first openly gay player.
The NHL and the players' union entered into a formal partnership with the You Can Play Project, an advocacy organization that fights homophobia in sports.
"We don't want any segment of society to feel alienated from the game, to be the subject of slurs, to feel uncomfortable, whether as a fan or in the locker room," NFL commissioner Gary Bettman said.
American media turned to two questions on Tuesday: How many active gay players are out there in the big sports leagues and who is next? The answer to the second question could be answered soon.
Obama told Collins he not only changed his own life but the lives of others. In the case of one football player, that seemed prophetic.
In the past, wary of reaction from team-mates and fans, players have waited until they retired before announcing they were gay. The most recent was Robbie Rogers, a US national team player.
In February, he announced he was gay on the same day he was retiring. But on Tuesday, he was back at training, accepting an offer to practice with the Los Angeles Galaxy.
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