Imane Khelif advanced to the quarterfinals in the 66kg category of women's boxing on Thursday after her opponent, Angela Carini of Italy, withdrew just 46 seconds into the fight.
Carini had gone to her coach after 30 seconds to fix her headgear but after briefly resuming the fight returned to her corner and withdrew.
Carini refused to shake hands with her Algerian counterpart Khelif and collapsed to her knees in tears after retiring from the bout.
In that short space of time, Khelif had landed two punches to the head. An Italian coach said afterwards that Carini had suffered a serious nose injury. The result was officially listed as an abandonment.
Disqualification at World Championships
Last year, Khelif was disqualified from the Women's World Championships in New Delhi, organized by the International Boxing Association (IBA). According to the DPA and AP news agencies, this came after testing found that her testosterone levels were too high, resulting in a failed gender test.
Also disqualified was Lin Yu-ting of Taiwan, who fights in the 57kg class. Lin was also stripped of her bronze medal.
However, in a statement issued on Wednesday, the IBA rejected reports that elevated testosterone levels were to blame.
"Point to note, the athletes [Khelif and Lin] did not undergo a testosterone examination but were subject to a separate and recognized test, whereby the specifics remain confidential," the statement reads.
"This test conclusively indicated that both athletes did not meet the required necessary eligibility criteria and were found to have competitive advantages over other female competitors."
However, due to governance, financial and ethical issues at the IBA, it's not the boxing federation but the International Olympic Committee (IOC) that is organizing the boxing events at the Paris Games.
IOC: 'Everyone complying with eligibility rules'
Earlier in the week, the IOC insisted that everyone competing in the women's category of boxing was complying with the eligibility rules set out for the competition.
"They are women in their passports, and it's stated in there that they are female," IOC spokesman Mark Adams said.
Khelif competed in the women's event at the Tokyo Olympics three years ago, finishing in fifth place. Lin also fought in Tokyo.
Criticism and support
The inclusion of the two fighters in Paris has not been without its critics.
"I don't agree with that being allowed, especially in combat sports as it can be incredibly dangerous," said Australian boxer Caitlin Parker, who is competing in the 75kg weight class and therefore will not face either athlete.
However, prior to Thursday's fight, the Algerian Olympic Committee condemned what it described as "malicious and unethical attacks directed against our distinguished athlete, Imane Khelif, by certain foreign media."
It also expressed compete support for her, saying the entire nation was behind Khelif.
Excluded over refusal to take testosterone-supression medication
These cases follow the long-running saga of South African runner Caster Semenya, who won Olympic gold in the women's 800 meters in 2012 and 2016.
Semenya has unusually high levels of testosterone and since 2019, World Athletics has required her to take testosterone-suppression medication to compete in the 800m. As she has refused to do this, she has not competed in the 800m in the past five years.