Coroebus claims St James's Palace Stakes in tight finish at Royal Ascot

The 10/11 favourite, with William Buick on board, narrowly denied Lusail, My Prospero and Maljoom as he added to his 2000 Guineas triumph at Newmarket in April.

Drawn low in stall two, the fear beforehand was whether the three-year-old would get boxed in behind the pacemakers - and for a moment turning in his supporters would have been sweating.

But the gap came for Buick's mount against the far rail with a furlong and a half to run, at which stage it looked like he would pick up and win comfortably.

However, Lusail refused to go down without a fight and My Prospero and Mighty Ulysses were both in there pitching to set up a grandstand finish.

In the end Coroebus found just enough for pressure to hold on by a head from Lusail, with My Prospero third and Maljoom coming from the clouds to finish a close-up fourth after being denied a clear run.

Appleby said: "The key thing today and I said to William, 'just get that position and don't lose it'.

"Therefore he was always just having to keep the revs under him and in doing so the horse got keener and keener, I just think it paid in the last 100 yards.

"If we want to roll it back to his two-year-old career in the Royal Lodge, he shot clear and paid in those last few yards; you've got to sit and you've to count to 10 and wait and William gave him a fantastic ride around there. It is the reason why he probably wasn't winning as impressively as you might like to have seen.

"It is going to be a big learning curve for him today, I was delighted with how he took it in the preliminaries - he has never been more than 20 minutes up the road out of Newmarket and those challenges have been put upon him and he has ticked the boxes."

On future plans, Appleby raised the prospect of a mouthwatering clash with unbeaten Queen Anne hero Baaeed.

He said: "The Sussex Stakes is a race that we have spoken about beforehand, that we'd potentially like to see Coroebus take on Baaeed. It is always a fantastic race, isn't it? The Sussex Stakes - the older horses and the three-year-olds taking each other on, and we were confident (beforehand) that we'd hopefully be doing that on the back of today. I think that is still very much in the conversation.

"As always we'll let the dust settle, and the discussions with His Highness (Sheikh Mohammed) and the team and we'll firm those plans up. On the evidence of what I have seen today he deserves to be there for sure.

"Baaeed was a very impressive winner, taking nothing away from him, but this was just our horse's fifth start of his career, and I thought it was a gutsy performance in a race that probably wasn't run particularly to suit us."