The Starspangledbanner colt was last seen winning the Cox Plate at Moonee Valley in Australia and prior to that took the Saratoga Derby in America.
The Longchamp run was the bay’s first for 190 days but he showed no signs of rustiness when travelling handily on the outside and quickening under Shane Crosse to shake off a field of Group winners and prevail by three-quarters of a length at 63-10.
Pia and Joakin Brandt’s Pretty Tiger was the runner up at 12/1, with Sealiway third at 7/2 for Francis-Henri Graffard. Skalleti briefly flattered from the rear but had to settle for fifth on this occasion.
“It was a great performance, Shane gave him a lovely ride,” O’Brien told Sky Sports Racing.
“The race didn’t set up perfectly for him and he managed it very well, I’m delighted for everyone at home.
“To come here at the start of the season with a win in a Group One like the Ganay is very special, I’m very proud of everyone and I hope it’s the start of a good season ahead.
“He has a very good constitution, it’s not every horse you could campaign the way this lad has been campaigned.
“I think it’s a testament to the horse’s mind, his versatility and his constitution to travel as much as he has and keep performing.”
The Tattersalls Gold Cup at the Curragh is next on the agenda, with the Prince of Wales’s Stakes at Royal Ascot also pencilled in the diary come June.
“There’s a pretty obvious programme for 10-furlong Group One horses through the summer, the Tattersalls Gold Cup will be the most likely spot for him next and then we will take it from there,” O’Brien said.
“We’ll take it one race at a time, hopefully we can have a good season.
“I think he won’t go further, the Prix d’Ispahan is here over nine furlongs so we could come back for that, but I think it is more likely we would go to the Curragh.”
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