A top-ranking women pool player has refused to play against anyone who is not biologically female in professional competitions.
Alexandra Cunha, who is the fifth-ranking female international pool player, was involved in yet another transgender row after the sport’s rules changed to allow men identifying as women to play last week.
Dozens of professional sportswomen have rebelled against the growing number of trans competitors, including in the women’s pool leagues.
Female competitors argue players who identify as women but were born male have an unfair advantage.
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Cunha, who is based in the UK but is captain of the Portuguese women's national pool team, told The Mail on Sunday: “I've been playing pool since I was 17 and I'm fifth in the world but I'm risking throwing everything away over this because I hate unfairness.”
She added: “I recently played a transgender player and I was destroyed when I lost.”
The 49-year-old pulled out of the International Rules Pool Tour, telling organisers: “As we live in a free world and I will stand up for what I believe is fair, I will not play against any players that wasn't born a woman independently of being a first round or a final.”
Cunha instead offered to participate in the event if the rules were reverted to accommodate her demands.
However, organisers only promised to refund her entry fee.
The controversy now rocking the top levels of women's professional pool began on October 24 when the World Eightball Pool Federation (WEPF) changed the rules over trans players' participation in female tournaments.
Both bodies stipulated they would operate a “self-identification policy” but would also reserve the right to test that testosterone had been suppressed to the levels required of trans athletes by the International Olympic Committee.
Another player, named Lynne Pincher, said: “When I heard the announcement last week I spent most of the day in tears - especially because it came after the announcement eight weeks earlier that it was finally going to be a fair field.
“I'm worried now about the future of the game for women.
“If next year we had eight trans players they would probably be in the top eight.”
Close-up of balls on pool table
Olympian Sharron Davies, who has been a vocal supporter of women's sports remaining single-sex, branded the decision to allow trans players to play in female pool competitions as “heartbreaking”.
She said: “Pool is a male-dominated sport, like so many, and these women have worked hard to get their own tour.
“These organisations know their game is sex-affected.
“They know women need their own tournaments to grow female participation and opportunities.
“They must show courage and decency and stand up for women.”