With that, Sam set himself on a path to become the first publicly gay player in the National Football League.
"I looked in their eyes, and they just started shaking their heads - like, finally, he came out," Sam said Sunday in an interview with the New York Times, the first time he has spoken publicly about his sexual orientation.
Sam, a 6-foot-2, 260-pound senior, went on to a stellar season for Missouri, which finished 12-2 and won the Cotton Bowl. He was named a first-team All-American. He was the defensive player of the year in the Southeastern Conference, widely considered the top league in college football. Teammates voted him Missouri's most valuable player.
Now Sam enters an uncharted area of the sports landscape. He is making his public declaration before he is drafted, to the potential detriment to his professional career. And he is doing so as he prepares to enter a league with an overtly macho culture, where controversies over homophobia have attracted recent attention.
As the pace of the gay rights movement has accelerated drastically in recent years, the sports industry has seen relatively little change, with no publicly gay male athletes in the NFL, the NBA, the NHL or MLB. Against this backdrop, Sam could become a symbol for the country's gay rights movement or a flashpoint in a football culture war - or both.
Sam, 24, is projected to be chosen in the early rounds of the NFL draft in May, ordinarily an invitation to a prosperous professional career. He said he decided to come out publicly now because he sensed that rumors were circulating.
"I just want to make sure I could tell my story the way I want to tell it," said Sam, who also spoke with ESPN on Sunday. "I just want to own my truth."
The NFL presents the potential for unusual challenges. In the past year or so, the league has been embroiled in controversies ranging from anti-gay statements from players to reports that scouts asked at least one prospective player if he liked girls.
Recently, Chris Kluwe, a punter, said that he was subject to homophobic language from coaches and pushed out of a job with the Minnesota Vikings because he vocally supported same-sex marriage laws. And last week, Jonathan Vilma, a New Orleans Saints linebacker, said in an interview with the NFL Network that he did not want a gay teammate.
"I think he would not be accepted as much as we think he would be accepted," said Vilma, who has played 10 seasons in the league.
At a showcase game for college seniors last month, several scouts asked Sam's agent, Joe Barkett, questions about whether Sam had a girlfriend or whether Barkett had seen him with women.
The league, which has a policy prohibiting discrimination based on sexual orientation (among other things), is the largest of the major sports leagues in the United States, with about 1,600 players on rosters at any time during the season. But it has never had a publicly gay player.
Over the decades, some players in the major sports leagues did little to conceal their sexual orientation, but they were not out to the public during their careers. A few players have come out upon retirement, like the NFL player Dave Kopay in the 1970s and the NBA player John Amaechi in 2007, both considered pioneers by many gay people.
Last spring, Jason Collins, a 12-year veteran of the NBA, mostly as a little-used reserve, came out after the season. A free agent, he has not been signed by another team.
Also last year, the soccer player Robbie Rogers, a former member of the U.S. national team who later played professionally in England, revealed that he was gay after he announced his retirement. Encouraged by the supportive response, he resumed his career, playing for the Los Angeles Galaxy of Major League Soccer.
Although Sam's professional prospects are far from certain, several NFL draft forecasters have predicted that he will be chosen in the third round. (Thirty-two players are selected in each round.) Rarely are players who are drafted that high cut by teams, and often they become starters, sometimes in their rookie year.
Between now and the draft, Sam plans to attend the scouting combine, where players are put through a gauntlet of physical and mental tests to judge their readiness for the NFL. Sam might be considered too small for a professional defensive end, meaning he would have to learn to play as an outside linebacker.
But it is reasonable for Sam to wonder what sort of impact - positive or negative - his declaration will have on his professional prospects.
"I'm not na?e," Sam said. "I know this is a huge deal and I know how important this is. But my role as of right now is to train for the combine and play in the NFL."
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