SEINE-SAINT-DENIS, France -- Taiwanese boxer Lin Yu-ting has guaranteed herself a medal after securing victory over Bulgaria's Svetlana Kamenova Staneva in the women's 57kg quarterfinals on Sunday.

Yu-ting has been the subject of an ongoing controversy in this year's Olympic boxing event, after the International Boxing Federation (IBA) claimed at last year's world championships that she and Algerian fighter Imane Khelif failed an unspecified eligibility test, although it has not given further details.

The pair are allowed to fight under the International Olympic Committee's (IOC) guidelines over gender eligibility. Both fighters are making their second appearance at the Olympics after fighting at Tokyo 2020.

"I know all of Taiwan's people are standing behind me and supporting me, and I will carry this energy to the end," Lin said after her win.

Heavy scrutiny began when Khelif won her opening bout within 46 seconds after her opponent, Angela Carini of Italy, tearfully abandoned the fight, although Carini has since apologized and said she backs the IOC's decision to allow Khelif's participation.

Khelif also has secured a medal, having won her 66kg quarterfinal bout against Hungary's Anna Luca Hamori on Saturday.

Yu-ting, who is the No. 1 seed in her weight class, achieved similar success on Sunday, winning a scrappy fight against Staneva. She is now guaranteed at least a bronze medal, with the chance to fight for gold next Saturday should she win her semifinal bout against Turkey's Ezra Yildiz Kahraman on Wednesday.

"Yu-ting is great!" Taiwan President Lai Ching-te wrote on his Facebook page after Lin's victory.

"In recent days, Taiwan's people have been indignant at the slander against her. Facing the challenge, Yu-ting is fearless and uses her strength to crush the rumors. Let us continue to cheer for her!"

IOC president Thomas Bach on Saturday defended Khelif and Yu-ting.

"Let's be very clear here: We are talking about women's boxing," Bach said. "We have two boxers who are born as a woman, who have been raised a woman, who have a passport as a woman, and who have competed for many years as women. And this is the clear definition of a woman. There was never any doubt about them being a woman."

The IBA has not been allowed to organize the Olympic boxing tournament since 2019 following a continued run of controversies. The body, which is led by an acquaintance of Russian President Vladimir Putin, has not released more details on the alleged tests, calling the process confidential.

The Olympic sport reached gender parity for the first time in Paris, inviting 124 men and 124 women just 12 years after women's boxing made its Olympic debut.

The Associated Press and Reuters contributed to this report.