An LGBT group has dropped tennis legend Martina Navratilova after she penned an op-ed against transgender athletes competing in women's sports.

Navratilova's column, titled “The Rules on Trans Athletes Reward Cheats and Punish the Innocent,” appeared in the Sunday Times of London.

In the column, Navratilova, who came out lesbian in 1981, called it “cheating” and “insane” for transgender women to compete in women's sports.

(Related: Martina Navratilova calls transgender athletes competing in women's sports “cheating.”)

Athlete Ally, a non-profit dedicated to ending homophobia and transphobia in sports, responded by dropping Navratilova from its advisory board and removed her from its ambassador program.

The group called Navratilova's comments “transphobic” and accused her of promoting “dangerous myths that lead to the ongoing targeting of trans people through discriminatory laws, hateful stereotypes and disproportionate violence.”

Navratilova has been a strong advocate for LGBT rights and has voiced her opposition to bills that would prohibit transgender people from using the bathroom of their choice.