John Gosden’s charge arrived unbeaten in three starts – with the trainer having opted to bypass the 2000 Guineas earlier this month in favour of a low-key return in a Newcastle handicap, which Palace Pier had duly won in style.
The Classic form was represented though, with Newmarket second and third, Wichita and Pinatubo, doing battle again, with the latter on a retrieval mission having relinquished his perfect record in the Guineas.
It was Wichita who set the early pace, with Ryan Moore taking up a prime position on the rail, while Frankie Dettori was happy to settle in the pack as Threat was the first to throw down his challenge in the straight.
He quickly dropped back as Pinatubo and Palace Pier (4-1) made their moves down the outside, with William Buick looking to have plenty of horse underneath him.
The 11-8 favourite edged in front of Wichita inside the final furlong, but Palace Pier found a little bit extra for the red-hot Dettori, pulling a length clear at the line, with Pinatubo taking second in a tremendous three-way finish.
Dettori was completing a memorable Group One double having earlier won the Coronation Stakes with Alpine Star, with Campanelle also triumphing in the Queen Mary Stakes.
The Italian said: "We've always thought a lot of him, but he's been a bit sleepy in the mornings and we were scratching our heads.
"It was very hard to even get him fit and John thought he'd send him to Newcastle for a handicap to wake him up and it did.
"We threw him in the deep end today, but we knew in the back of our minds he was a good horse in a big body - we just weren't sure how good he was.
"I went wide, round the whole field and he galloped out good. It looked like the Guineas form stood up and he showed me today potentially what I thought he was going to be. He's so laid back he could probably get 10 furlongs, but at the moment a mile is what he wants and I'm sure John will have a plan."
He added: "To equal Pat Eddery's record of 73 (Royal Ascot winners) is special. I sat next to him for 15 years, he was one of my heroes, his nickname was God so it gives me great satisfaction."
Gosden - officially crowned top trainer for the week - said: "The race panned out well. Frankie said he wanted to ride him a little cold and settle him, as he knew there would be a searching pace to stretch it. Arizona and those boys were in there for Wichita.
"It got a little bit rough inside and Frankie avoided all of that and swept round the outside. It was no fluke, he is a very talented horse. We are going to point to the Jacques le Marois that his father (Kingman) won at Deauville. I think it would have been madness to throw the horse into the Guineas with no experience of that kind of level of competition.
"If he had gone to a Dewhurst or Jean Luc Lagardere (at the end of last season) it would have been fine, as he would have had the experience, but you can't go winging in there off novices. I deliberately said not to do that, as he is a lovely horse.
"We knew he would like this track as it is a stiff mile and consequently that's why we were keen to bring him here after Newcastle. Luckily we got that race at Newcastle which set him up for this.
"It's a stiff old mile at Ascot and he showed his stamina. Pinatubo looks like going for the Sussex, all being well for him. He's that sharper type of horse, king two-year-old. Goodwood is a totally different mile to the Ascot mile."
Of Pinatubo, Charlie Appleby said: "It is disappointing to get beat again, but he travelled and we saw the Pinatubo we saw last year, for sure.
"From the three to the two it is just a matter of pressing the button again. William said just on that ground in the last 100 yards the tank was emptying out. He is so courageous he held on for second still.
"As always we will get him back and speak to the connections. Everyone likes to put the gun to people's head (for plans) after the event, but the Sussex is an easy mile there and we have seen what he can do around that track. That is always an option.
"He is still a class animal at the end of the day and we are not going to write him off yet. You can see when he walked in he had given it everything. When he turned in and got him filled up between the three and the two we are back at the days of old."Last chance to get your free month trial of Racing TV! Every race live from over 80 meetings from some of the best British and Irish racecourses. Click here for more details.
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