Japan's bantamweight boxer Satoshi Shimizu has had his controversial defeat to Magomed Adulhamidov of Azerbaijan overturned.
Shimizu now goes through to the last eight where he will face Algerian Ouadhi with a medal on the line for the victor.
The Japanese fighter was 12-5 down going into the final round when he knocked down his opponent five times.
Abdulhamidov was also docked two points, but Shimuzu only won the round 12-10.
The International Boxing Association say the contest should have been stopped and is investigating how the result came to pass.
This was the biggest, but by no means the only, controversial incident in the boxing ring on Day Five.
Iranian heavyweight Ali Mazaheri was disqualified for being warned about holding three times in a minute against Cuban Jose Larduet Gomez - leaving the boxer shocked and the crowd expressing its disenchantment noisily.
Australians 17-year-old Jai Opetaia and Ibrahim Balla could also count themselves unfortunate not to progress.
Opetaia put in a tremendous display against the world number one fron Azerbaijan Teymur Mammadoc and was unlucky to lose 12-11.
Balla slammed his opponent Detelin Dalakliev after losing 14-10, a baffling scoreline as the Aussie bantamweight went into the final round one point down before dominating the last stanza.
"How can you be down in the last round when you throw two times, three times as many punches as the other guy and he runs away like a coward?"