Three months after coming out publicly, the 6'2" Texan, a defensive end last season for Missouri, was picked Saturday by the St. Louis Rams in the seventh round of the NFL draft to become the league's first openly gay player.
His emotional reaction to hearing the news was caught on camera. Watch below as he breaks down in tears and shares his joy with his boyfriend, Vito Cammisano.
"Right now I'm just focused on football, playing in the NFL," Sam, 24, told PEOPLE in an exclusive interview days before the draft. "I'm not nervous. I'm used to it. I'm excited. I'm ready to get back to work."
Sam's announcement in February that he is gay thrust him into the spotlight. But despite winning honors as last season's defensive player of the year in the Southeastern Conference, some considered him too small for the defensive line in the pros, and a poor showing in the NFL's combine earlier this spring raised questions about his prospects.
But he never wavered in his goal to take his game to the next level.
"I know how to play this game," he said. "I love this game. I have great respect for this game."
That respect extends to teammates and coaches who did not take issue with his sexuality after he told them at the start of his senior season.
"They already knew," he said. "But I guess actually saying it out loud to your teammates, it's kind of different. I was like, 'Okay, sorry guys, just wanted to tell ya.' I just walked off and that was it. It wasn't a shock to anyone."
"But it was a scary moment; it was a relief moment. I could say this out loud: 'I'm gay.' "
"In the end, all that mattered was winning games and winning championships, which we did," he said. "We were one game away from the national championship. It shows how a team can come together."
Now that he's an official member of the NFL, he hopes that his example, as both a player and a teammate, will continue to inspire others.
"I'm a competitor and I love to compete and I love challenges," he said. "This will be just another challenge."
"I'm comfortable in who I am. And I'm proud of who I am. I don't think I'm different from anybody else.' "
For more on Michael Sam and a portfolio of gay professional athletes on their choices to play and live openly, pick up this week's issue of PEOPLE, on newsstands May 14.
Reporting by MARY GREEN