The 23-year-old was eight seconds away from being crowned Britain’s first Olympic taekwondo champion when his opponent, Ulugbev Rashitov of Uzbekistan, struck him with a swivelling kick to the head and a follow-up to the body.
Sinden crashed to the mat, heartbroken, his dreams of Olympic gold shattered. Silver was no consolation.
“I went for the gold, so the ultimate emotion was disappointment,” reflects Sinden, nine months on.
That silver quickly became his motivation – “fuel to go and win gold in Paris” – but there is also growing pride at what he accomplished and what he wants that Olympic medal to mean.
“Most people watched us at the Olympics, they saw how intense the fights are, how one second you’re winning, one second you’re losing and how quickly a fight can change,” he says.
“It’s electric. Especially with my fights, there’s never a dull moment. Taekwondo became such a massive spectacle at the Olympics, everyone was messaging me saying ‘it’s my new favourite sport, when can we next watch it?’”
Well to those excited inquisitors, here is the answer – later this month across the Pennines when the European Taekwondo Championships are staged between May 19 and 22 at the Manchester Regional Arena.
“For those who watched the Olympics on telly, this is your time to come and support us and get that feel in real life,” urged Sinden.
“It’s good seeing it on the telly but when you’re there in person with the crowd screaming and shouting it just takes it to the next level.
“That’s why I’m glad we’ve been able to get the Europeans in our own back yard.
“It’s about getting as many people realising that we’re here and that taekwondo is a sport to be watched.”
The four days of the European Championships will follow a similar format to that of the world championships which were staged in the same arena three years ago and ended in a lot more uplifting fashion for Sinden.
Back then, the 20-year-old who’d first tried the sport aged four when he was dragged along to his older sister’s lessons, was crowned world champion in front of his home fans.
“It was a great experience fighting in front of that home crowd, a prestigious event like the world championships was something else,” he said.
“It was a great atmosphere, everyone involved made it such a good spectacle, the best I’ve been to both as a fighter and a fan.
“On top of that how well the sport was received in the Olympics, since the worlds there’s not been a competition as big with a crowd. We can’t wait to get our friends and family back in and get that home advantage for the European Championships.”
Sinden will compete in the 68kg event on the Saturday (21st). At an Olympics, each weight division takes one day, but in Manchester athletes can fight over two days the longer they stay in the tournament.
“The Olympics is all one ring, but at the Europeans it’s one hall and it’s not just Olympic athletes, we also have para-athletes competing as well, the first time it’s been fully integrated. So fans will get to cheer on the whole team.
“We train together, so it’s about time we compete together.
“Back at the worlds in 2019, for the finals they sectioned the rest of the venue off and made it a sphere for the fight. How they did that was amazing.
“Pitch black and with the crowd lit up in your colour, you saw how packed out it was and it made me think I need to put on a show here.”
Sinden certainly did so at the worlds and as the road to Paris intensifies with these championships, he hopes to deliver again.
“For me it’s about the performance, not the medal,” says Sinden.
“If I put the performance in the reward will come, taking it fight by fight and imposing my A game on my opponent.”