Cause Of Causes made light work of very testing conditions to give Ireland victory in The Ladbroke at Ascot.
The Gordon Elliott-trained four-year-old sprouted wings between the last two flights, as gallant top-weight Petit Robin appeared as if he had done enough.
Davy Condon's mount looked as if he had just joined in and rattled past Nicky Henderson's runner after the last, winning by four lengths from his fellow 25-1 chance.
Elliott said: "We were worried about the ground, but we thought he had a right chance if he did handle it.
"We brought him over a couple of days earlier as he's not a great traveller. The lads have worked with him at home and everyone has done a great job with him.
"We're not bothered what the handicapper does now as this was a good pot. He's a gentleman of a horse to deal with and it's nice to win a high-profile race.
"He could maybe go for the Betfair Hurdle at Newbury and could even be a horse for something like the Ebor in the summer."
Condon, who was given a four-day whip ban (January 6-9), added: "He wouldn't be in love with that ground but he had to go through it like the rest of them.
"He's so genuine and when I pulled out wide up the straight he flew. I was struggling turning in but when I pulled him out, he took off. I thought at the second-last I would win.
"He deserved a big one. He's been second in a Galway Hurdle and third in the Greatwood."
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