Defensive end Michael Sam of the University of Missouri became the first openly gay player to be selected in a National Football League Draft when he was taken in the seventh round by the St. Louis Rams on Saturday (US time).

Sam, the co-defensive player of the year in the Southeastern Conference who announced he was gay in February, would become the first openly gay player in the NFL should he make the team's 53-man regular-season roster this summer.

The defensive end was taken on the 249th pick in the last round of the three-day draft.

Television cameras captured Sam receiving the phone call informing him of his selection, the Texan breaking into tears and shaking with joy at the news.

"Thank you to the St. Louis Rams and the whole city of St. Louis. I'm using every ounce of this to achieve greatness!!" He posted on his Twitter account.

At a post-draft news conference, Rams coach Jeff Fisher said the Rams were lucky a player of Sam's ability was still available in the seventh round, and added that he had no concerns that Sam's sexuality - or media interest in him - would be a distraction to the team.