The opponent of boxer Lin Yu-Ting produced a controversial gesture after losing to the Taiwan fighter in the women's featherweight semi final on Wednesday.
Lin, along with Imane Khelif of Algeria, have both been involved in one of the key talking points at the Olympics in Paris.
Amid a gender eligibility row, both fighters have reached their final of their respective weight classes and could win a gold medal.
Having been disqualified from the World Championships by the IBA (International Boxing Association) after they said they failed unspecified gender tests, they were cleared to compete in Paris.
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Their participation has caused almighty uproar and Lin's latest opponent Esra Yildiz Kahraman stoked the fire.
Lin saw off the Turkish fighter with an unanimous decision victory and there appeared to be respect between the pair as they touched gloves and Yildiz opened the ring ropes for the 28-year-old to exit.
However, after Lin had gone off for a medical assessment, Yildiz then returned to the middle of the ring, removed her gloves and performed an 'X' gesture with her index fingers.
The action followed on from Bulgarian boxer Svetlana Staneva staging a protest with the "double tap X symbol" after her loss to Lin in the previous round.
The Telegraph said Staneva's antics were an "apparent reference to her female chromosomes" as the gender row continues.
Females have two X chromosomes, while males have X and Y.
Yildiz did not respond to her behaviour, while a "no comment" reply was provided by her team when members of the media asked for an explanation of the gesture.
SPORTbible has reached out to the Turkish Boxing Federation for comment.
Khelif's final is on Friday when she goes against Yang Liu of China in a prime-time clash.
Lin, who is making her first appearance in an Olympic final, returns to Roland Garros and takes on Poland's Julia Atena Szeremeta on Saturday evening.
Josh Lawless