Great Britain's Mahama Cho had his Tokyo 2020 taekwondo gold medal dreams ended early by China' Sun Hongyi as the heavyweight exited in the Round of 16.
Cho was defeated by the Chinese competitor on Golden Points in a surprise early exit.
The 31-year-old could yet still secure a medal despite losing 7-4.
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Should Sun Hongyi advance to the final of the +87kg competition at Makuhari Messe Hall then Cho would be entered into the repechage rounds.
Cho took an early 4-2 lead in Round 1 of the match, but Sun levelled things up in Round 2. A scoreless Round 3 followed but Cho was knocked out after Sun struck the first blow in Golden Point overtime.
The result continued an up-and-down campaign for Team GB in taekwondo at Tokyo 2020.
Jade Jones missed out on an historic three-peat as the two-time defending champion was knocked out by Kimia Alizadeh.
The Refugee Olympic Team representative stunned Jones 16-12 to end her gold medal defence in Jones' her first match of the Olympics.
Jones suffers shock defeat, Walkden left in tears
Cho had been mentioned as a potential medal contender after winning a silver at the 2017 World Championships in South Korea.
Teammate Bradly Sinden had earlier in these Olympics won silver in the featherweight class.
Though perhaps the highlight so far for Team GB in the dojang was Lauren Williams' silver medal in the -67kg division.
The 22-year-old was disappointed to just miss out on a gold medal as Matea Jelic landed two late head kicks to secure a narrow 25-22 victory.
“I had her with 10 seconds to go, but I messed up and that’s on me," said Williams. I knew I was winning, but I didn’t know there was only 10 seconds left.”
“I made a mistake and she reacted and I’ve got to accept that and move on. It was a mental block.
"It happened on the biggest stage of my career, that’s a hit, but hopefully it will never happen again.”
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Bianca Walkden competes later on Tuesday in the women's heavyweight competition.
Reigning world champion Walkden's first match comes at the quarter-final stage against Cansel Deniz of Kazakhstan.
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