Joseph O'Brien secured his first Royal Ascot winner as a trainer as State Of Rest led from pillar-to-post in the Prince of Wales's Stakes.
Already a Group One winner in America, Australia and France, the Starspangledbanner colt was last seen finishing a close-up third when bidding to bag a first top-level prize on European soil in the Tattersalls Gold Cup at the Curragh.
With the fast-improving Bay Bridge, Japanese raider Shahryar and a previous winner of the race in Lord North in opposition, State Of Rest was a 5-1 shot and proved his class under Shane Crosse.
Sent straight to the lead, the four-year-old steadily raised the tempo and had seen off the challenge of Dubai Sheema Classic winner Shahryar early in the home straight.
Ryan Moore delivered 10-11 favourite Bay Bridge with what looked like a well-timed run, but try as he might, he could never quite get on terms with State Of Rest who found plenty in front to prevail by a length.
O'Brien won the Prince of Wales's Stakes as a jockey 10 years ago aboard So You Think, trained by his father Aidan.
O'Brien told ITV Racing: "It was a brilliant ride from Shane. State Of Rest is a very tough horse. We had a good chat with Shane and decided to make the running. It could not have worked out better.
"I thought Shane gave him a marvellous ride. He got the fractions perfect and he is a top horse.
"It's very special. It's been a long time coming (first Royal Ascot win as a trainer). We've had a lots of horses run well here, but it's special to get a winner here and not only a winner, but to win a race like the Prince of Wales's Stakes is hugely special. We have a great team of owners and a special horse."