FC Dallas goaltender Chris Seitz has become one of the first three Major League Soccer players to join Athlete Ally — a national organization dedicated to ending homophobia in sports.

Seitz has signed the group’s pledge along with the Los Angeles Galaxy’s A.J. DeLaGarza and Omar Gonzalez, Athlete Ally announced.

In 2012, Seitz was named Major League Soccer’s Humanitarian of the Year after he cut his season short to become a bone marrow donor. Seitz, who will turn 26 on Tuesday, was the first player taken in the 2007 MLS SuperDraft.

“As an athlete, I’ve learned first hand what leadership means and seen how small actions can make a huge difference,” Seitz told Athlete Ally. “By joining Athlete Ally, I hope my voice will reach gay, lesbian, bisexual and transgender youth and remind them that they are welcomed and respected in sports.”

Hudson Taylor, executive director of Athlete Ally, said: “As our first professional soccer players to join Athlete Ally, and following the brave choice of fellow pro soccer player Robbie Rogers to come out, A.J., [Omar] and Chris’ voices as allies supporting LGBT teammates and fans are so important. Their commitment demonstrates how MLS is a leader among professional sports leagues in the LGBT rights movement.”