The National Football League (NFL) has banned discrimination based on sexual orientation.

The addition was included in the league's 2011 collective bargaining agreement, which was approved by the league's owners and the NFL Players Association (NFLPA) on July 25, first reported.

“We certainly believe, speaking for the Players Association, that we have a tremendous social and cultural impact. We definitely understand the effect that we have on society and culture, and we feel we have a responsibility to have very high standards. With something like discrimination of any kind, we just wanted to make sure we are a symbol for good,” George Atallah, a spokesman for the NFLPA, was quoted as saying by the Huffington Post.

While no professional athlete in the United States has come out gay during his or her career, earlier this year former Phoenix Suns CEO Rick Welts announced he's gay. And over the past couple of years, several straight athletes have openly advocated for gay rights, including New York Rangers winger Sean Avery, Phoenix Suns point guard Steve Nash, New England Patriots safety Bret Lockett, Carolina Panthers linebacker Nic Harris, New York Jets cornerback Antonio Cromartie, former Giants defensive end Michael Strahan, Washington Redskins wide receiver Donte Stallworth, Cleveland Browns linebacker Scott Fujita and Baltimore Ravens linebacker Brendon Ayanbadejo, to name a few.