Defending champion Bakhodir Jalolov beat Australian Teremoana Junior to progress to the super heavyweight semifinals on Friday as a gender row rumbled on over the participation of Taiwan's Lin Yu-ting at the Paris Olympics.
In a thrilling clash, Jalolov attempted to keep his distance from the Australian in the first rounds and strike from afar, but Teremoana was able to get in close and land a few jarring shots.
The towering Uzbek was more combative in the second and third rounds, connecting with clean shots while taking less damage as he claimed a 5-0 win and ensured himself a second Olympic medal.
"I am so happy today I won. It was very great because I won a second medal," Jalolov told reporters.
"I will not stop, I will continue until the finish. In the Olympics, there are no easy fights. Only hard ones."
Teremoana said he believed that he had won the first and third rounds.
"Obviously, the judges didn't see it the same way," he said. "Such is life, just got to take it on the chin and get better."
In the first bout on Friday, Taiwan's Lin beat Uzbekistan's Sidora Turdibekova by unanimous decision.
Asian Games and double world champion Lin and Algeria's Imane Khelif have both been cleared to compete despite being disqualified at the 2023 World Championships after failing International Boxing Association eligibility rules that prevent athletes with male XY chromosomes competing in women's events.
Khelif won her round of 16 welterweight bout on Thursday when Italian opponent Angela Carini quit after 46 seconds.
Lin was never threatened during her fight with Turdibekova and landed a big right in the second round that rattled the Uzbek before taking the win.
David de Pina made history with his flyweight quarterfinal win over Zambian Patrick Chinyemba, ensuring a first Olympic medal for Cape Verde - a nation with a population of some 600 000.
Local hope Billal Bennama beat Cuba's Alejandro Claro on a split decision in a men's flyweight quarterfinal, ensuring another medal for France after Sofiane Oumiha's win on Thursday.
Claro's defeat left Olympic boxing superpower Cuba with just two boxers in the competition - Erislandy Alvarez and twice Olympic champion Arlen Lopez Cardona.
The country last won fewer than three boxing medals at the 1968 Olympics in Mexico City.
Lopez Cardona ensured a second medal for Cuba on Friday, beating Uzbek Turabek Khabibullaev to set up a mouthwatering clash with Tokyo silver medallist Oleksandr Khyzhniak in the semi-finals.
Ukrainian Khyzniak scored a unanimous win over Brazilian Wanderley Pereira in their light heavyweight bout, while Uzbek 2016 gold medallist Hasanboy Dusmatov and 2020 silver medallist Nesthy Petecio of the Philippines also claimed victories.