China's Cheng Huang has won gold in the men's ASM1x single sculls as Britain's Tom Aggar was beaten for the first time since 2008.
After taking the lead halfway through, Huang powered home in a time of 4:52.36.
Australia's Erik Horrie came second and Aleksey Chuvashev of Russia won the bronze medal.
British rower Aggar, who has not been beaten since the Beijing Paralympics, finished in fourth place and said that he was disappointed with the result.
"I'm devastated. I was obviously the favourite going in and I wanted to win," Aggar told Channel 4.
"I went out hard but my race fell apart in the middle. I tried to dig deep towards the end but I had nothing there.
"It just wasn't my day today."
Aggar had been one of the favourites for a British gold medal.
