Dharma Rain, ridden by Jack Tudor, was seventh when she passed the post but stewards stripped victory away from Just Henny and disqualified the rest for failing to jump the third-last hurdle where a horse Bluebell Sally had pulled up injured.
When the field approached the same hurdle on the next circuit, stewards held fluorescent yellow arrows to direct runners around the injured horse but all jockeys except Tudor assumed it was an instruction to avoid the hurdle.
"It was made very unclear, it wasn't done brilliantly at all," Tudor told Sky Sports. "It looked as if the markers were in the correct position, it was a 50-50 call.
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"I jumped it... The others missed it, but I could see that the markers were behind the hurdle, so I went with my gut instinct and jumped it."
Page Fuller, who was riding Queen Among Kings and in the lead group, thought otherwise.
"The horse broke down at the hurdle, I was further back in the field and from where I was, the markers looked like they were in the hurdle," Fuller said.
"There was a flag being waved... But until you got around the hurdle, you couldn't see they were behind."
After a thorough investigation, Dharma Rain was declared the winner as the only finisher but British Horseracing Authority Stewards said no penalties would be imposed taking into account the poor visibility in the rain. (Reporting by Rohith Nair in Bengaluru; Editing by Michael Perry)
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