The Olympic judo quarter-final between world champion Masashi Ebinuma and Cho Jun-Ho of South Korea descended into farce on Sunday after Cho was awarded victory only for his Japanese rival to be declared the winner moments later.
The fight remained level after a five-minute contest plus an extra three minutes of golden score, meaning it went to a judges' decision.
All three judges on the mat awarded the bout to Cho, clad in blue, but the International Judo Federation's Refeering Commission then intervened.
Following frantic discussions on the sidelines, referees director Juan Carlos Barcos, who had been seen consulting federation president Marius Vizer, called the judges over and told them to change their minds.
The three judges then went back onto the mat and having originally all lifted blue flags denoting a Cho victory, this time thrust up three white ones instead.
Ebinuma was declared the winner and will fight Georgia's Lasha Shavdatuashvili in the under-66kg semi-final.
Federation General Secretary Jean-Luc Rouge told AFP the move had been necessary to ensure the right fighter won.
"The referees weren't told to change their minds, they were merely reminded about an incident (an attack by Ebinuma that could have scored) that should have influenced their decision," he said.
"It had escaped their minds but having reconsidered it they then gave their modified verdicts."
When put to him that the incident had been damaging for the federation, Rouge added: "It's better that the federation is damaged rather than judo."
The crowd, who were upset over the original decision anyway and jeered loudly, became even more vocal following the farcical overturn and Cho was afforded a standing ovation as he left the mat.
Already, during golden score, the referees commission had overturned the award of a winning score for Ebinuma by the judges -- the incident the commission then reminded the judges to consider in their decision.
For the first time at the Olympics, video replay technology is being used to review contentious scoring but the over-rule of a judges decision following a draw has never been done before.