Lewis Ferguson walked away uninjured after a spectacular fall from Merrion Square in the John Dufosee Memorial Open Hunters’ Chase at Wincanton.
The Paul Nicholls-trained nine-year-old looked likely to win approaching the final fence when jinking and unseating the amateur rider.
Despite being nearly stood up on the turf, Ferguson was fired into the fence and his momentum shot him in to the air where he completed a somersault before crashing to the ground.
Officials began to get the screens out, anticipating Ferguson would require medical assistance, but he remarkably got to his feet and walked away unscathed.
Coombe Hill won at 4-1 for trainer and former jockey Chris Honour. Wincanton clerk of the course Barry Johnson described it as "the worst fall I've ever seen."
He said: “Lewis is absolutely fine, unbelievably.
“He walked into the parade ring and was chatting away as if nothing had happened, calm as you like. “It was amazing, I’ve never seen anything like it. It was certainly the worst fall I’ve ever seen and I’m just glad he’s all right because I feared the worst.”
It was only the 18-year-old Ferguson’s fifth professional ride, and he tweeted afterwards saying: “Would just like to thank everyone for the messages!! Bit of a sore head but on the whole absolutely fine!!”