Marcus Tregoning registered a first Royal Ascot success since 2003 as Perotto landed the Britannia Stakes.

Derby-winning trainer Tregoning had endured a drought since High Accolade won the King Edward VII Stakes in a year he saddled a double, with Nayef – possibly the best horse he ever trained – winning the Prince of Wales’s Stakes.

Perotto had his stamina to prove racing over a mile for the first time – which was a marked rise in trip from his two-year-old days when he even ran over five furlongs in the Flying Childers.

Settled at the rear of the pack by champion jockey Oisin Murphy, there was little between the two groups and Perotto made a bold move a furlong out.

Joseph O’Brien’s Liffey River was charging home late but failed to get there by half a length, with Quintillus and Dubai Honour fourth.

Murphy said: “I thought I was Jamie Spencer and missed the break by a couple of lengths. I tacked over to the rail and followed William Buick which was the right decision.

“He put his little head down and his ears back when the pace collapsed. He hit the line hard and could be a horse for Hong Kong.”

He added: “I don’t team up with Marcus very much, but he’s a top trainer with a small string and an absolute gentleman.

“This horse was very well prepared today, he gave me a super ride, I’m thrilled, these races are hard to win.

“He stuck his head out, I wasn’t sure about a mile and I rode him very cold.

“I wasn’t given any instructions, but I’m glad it worked out.”

Tregoning said: “We discussed plans and decided to drop him out and try to use his electric burst of speed late.

“Oisin is a top-class jockey and we were lucky to get him for our only runner at the meeting.

“This horse is from the same family as Accidental Agent and lots of other good ones, and showed he stays the mile really well.”

The famous Juddmonte silks were carried to a poignant victory by Ralph Beckett’s Surefire (5-1) in the King George V Stakes.

It was a first Royal Ascot success for jockey Hector Crouch and possibly a final one celebrated by Teddy Grimthorpe, who steps down from his long-standing role as racing manager to the late Khalid Abdullah on Saturday.

A winner at Leicester 10 days ago, for which he picked up a penalty, the Fastneck Rock colt came with a run down the outside and held off the strong late challenge of Ryan Moore on Sir Lamorak to win by a neck.

Crouch said: “I wanted to get him rolling and to the outside and I knew he would be hard to stop.

“It’s such a privilege to ride in the Juddmonte silks – it’s my second winner for them and the first was only last week at Leicester.”

Beckett said: “He’s still a bit green, and showed that at Leicester last week.

“He did just lean in as he was about to hit the front, but it was too far out for the dreaded claxon to sound.

“He’s been a bit of a slow burner, but saw out this tough trip and I hope he will end up a Leger horse.”

The closing Buckingham Palace Stakes went the way of John Quinn’s Highfield Princess (18-1), providing jockey Jason Hart with a first winner at the meeting.

Hart said: “She’s just kept working her way up from 57 last year to 92 and has improved with racing. I think she could be a black-type filly.

“I think the way the race panned out suited her. And the rain is getting into the ground and that helped. She’s an honest filly.

“I didn’t think my turn was going to come here, but thankfully it has with this filly.”