Jason Collins is calling it a career.

The NBA's first openly gay player announced his retirement in an article for Sports Illustrated titled "Parting shot: Jason Collins announces NBA retirement in his own words."

Collins played in the NBA for 13 seasons but it took him until 2013 to publicly announce his sexuality.

"It has been 18 exhilarating months since I came out in 'Sports Illustrated' as the first openly gay man in one of the four major professional team sports," Collins wrote in the piece. "And it has been nine months since I signed with the Nets and became the first openly gay male athlete to appear in a game in one of those leagues.

Collins played for seven different teams and appeared in 735 games. He mostly played center, but played power forward for one season with the Nets.

For his entire careeer Collins only averaged 3.6 points per game, but his presence was definitely appreciated on the Nets, a team that kept him for almost seven full seasons.

Wednesday night, Collins will officially announce his retirement at the Brooklyn Nets-Milwaukee Bucks game in Brooklyn. Jason Kidd, now coach of the Bucks, was his supportive teammate.

"The day will be especially meaningful for me because the Nets will be playing the Bucks, who are coached by Jason Kidd, my former teammate and my coach in Brooklyn," Collins wrote. "It was Jason who cheered my decision to come out by posting on Twitter: 'Jason's sexuality doesn't change the fact that he is a great friend and was a great teammate.'"

After Collins' announcement, an NFL drafted player, Michael Sam came out as gay as well. Sam was drafted by the Rams, but has since been cut twice and is without a team.

Tonight's Nets-Bucks game will be played at 7:30 p.m. ET and will be broadcast on the YES network in New York and FSN-Wisconsin in Wisconsin.