Winner of the St James’s Palace Stakes 12 months ago, the Aidan O’Brien-trained Circus Maximus went on to suffer a narrow defeat at the hands of Too Darn Hot in the Sussex Stakes before landing the Prix du Moulin and finishing fourth in the Breeders’ Cup Mile.
The four-year-old was the 4-1 favourite to double his Royal Ascot tally, just ahead of John Gosden’s recent Newmarket-winning filly Terebellum and the big two fought out a thrilling finish.
There was little to choose between the pair entering the final furlong and no quarter was given by either horse, with Ryan Moore aboard Circus Maximus and Frankie Dettori on Terebellum both in full flight.
As the line loomed, Circus Maximus just began to get the better of the argument and was a head in front where it mattered.
Marie’s Diamond was three lengths away in third.
O'Brien said from his Ballydoyle base in County Tipperary: "I'm delighted. That's him exactly - he's very tough. He quickened and then toughed it out, it's unbelievable really. Ryan gave him a brilliant ride.
"It's very exciting. Ascot is usually a very busy week for us, so it's brilliant today to see all the preliminaries and everything."
"There's a lot of stuff we are getting to see that we wouldn't if we were at the races. We've got a great team of people doing everything when we're not there. We couldn't be happier."
He added: "He's a very good horse and has a great pedigree. He has pace, he's tough and he's brave. He's a trademark Galileo with loads of speed.
"I think he is an underestimated horse. He's a very solid horse and his best form is at a mile which makes him more valuable. He's able to jump and travel early and he loves getting eyeballed. He toughs it out really well.
"A mile is his trip. He's lazy which is why he wears blinkers. It's only when the tempo is really strong like that he really focuses. The problem with mile-and-a-quarter and mile-and-a-half races is the tempo is not strong enough and you can't get him to focus.
"He's like a fighter. If you don't get his blood up he doesn't really bother. A mile is what he's comfortable at. I'd imagine he'd stay at that trip. The pace of the mile races gets his blood up.
"I'd say the Sussex Stakes is the race for him and he's comfortable racing round a bend as well."
It was a 59th Royal Ascot success for jockey Ryan Moore who said: "He is a very straightforward horse. He won the St James's Palace here last year and won the Moulin at Longchamp. He has been a really good horse and this is his third Group 1.
"They had their chance to come and beat him, but he battled away and fought all the way. I am delighted with what he has done today.
"He won the Dee Stakes and ran a good race in the Derby, he was sixth and wasn't beaten far. And as I said that is his third Group 1 and I delighted with him.
"I would say it is good ground, just maybe a bit slower, just on the slow side.
"We're very happy that we are here racing, the [lack of crowd] does detract from it all, but that is the way of the world at the moment."
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