Ballydoyle's Russian Emperor finished with a rattle to claim a last-gasp success in a thrilling renewal of the Hampton Court Stakes at Royal Ascot.

Runner-up to stablemate Cormorant when hot favourite for the Derrinstown Stud Derby Trial at Leopardstown last week, Aidan O'Brien's colt was sent off at 100-30 for what looked a competitive Group Three event.

Berlin Tango - who had beaten Tuesday's King Edward VII Stakes winner Pyledriver on his latest appearance at Kempton - travelled strongly into the home straight under Oisin Murphy before quickening to grab the lead.

It looked as though Frankie Dettori would carry the colours of the Queen into the winner's enclosure after his mount First Receiver eventually mastered Berlin Tango inside the final furlong.

However, it was Russian Emperor who came home best down the centre of the track to get up and beat the market leader by half a length - providing jockey Ryan Moore with his 60th Royal Ascot success.

Moore said afterwards:: "He's a really nice colt and has a lovely attitude. His dam (Atlantic Jewel) was very good - she was a champion in Australia.

"He won his maiden at Naas, and the last day at Leopardstown the ground was very quick and it was hard to make up ground.

"He was very professional today. I think 10 furlongs is fine, but he may get a little bit further - he'd give himself every chance to stay.

"I think he'll be a nice horse going forward for the rest of the year." 

In the day's big race, Lord North produced a devastating turn of foot under James Doyle to run out a convincing winner of the Prince of Wales's Stakes for John Gosden.

Bangkok made the running with Addeybb and Japan close up, while James Doyle was happy to sit Lord North (5-1) at the rear of the seven runners.

Earlier, champion jockey Oisin Murphy opened his account at the meeting with victory aboard Sir Busker in the Silver Royal Hunt Cup.

A big field of 22 runners went to post for the straight-mile opener on day two of the showpiece meeting, with Maydanny and Ouzo the joint-favourites at 4-1.

The former managed to battle his way to the front in the group that raced on the far side of the track, but it became clear racing inside the final furlong that the near-side group held a clear advantage.

The William Knight-trained Sir Busker was a 12-1 shot off the back of a narrow victory at Newcastle a fortnight ago and finished with gusto to get up and score by three-quarters of a length from Salayel. Alternative Fact and Almufti finished third and fourth respectively.

Jim Crowley took his winning tally for the meeting to four as Owen Burrows' Hukum ground out victory in the King George V Stakes - adding to his jockey's Tuesday treble.

Crowley had Hukum going well on the rail, just in behind the leaders, entering the straight.

They challenged two furlongs out and held on by half a length at 12-1 to defy a strong late challenge from joint-favourite Kipps and give owner Hamdan Al Maktoum a fourth winner of the meeting too.

Dark Vision was a length-and-a-quarter winner of the Royal Hunt Cup, under William Buick for Mark Johnston.

The four-year-old, owned by Godolphin, had finished second on his seasonal return at Newcastle this month to Sir Busker - winner of the Silver consolation race which had opened the card.

Dark Vision prevailed at 15-2 from Montatham - with Pogo and Vale Of Kent third and fourth respectively, and a gap back to the remainder of the 23-strong field.

Doyle doubled up with a length-and-a-quarter victory in the Windsor Castle Stakes on board Tactical, for Queen Elizabeth and trainer Andrew Balding.

The first two-year-old race of this year's meeting had an apt Royal winner as the 7-2 favourite collared eventual third Muker (40-1) in the final furlong, with Yazaman running on late to snatch second at 20-1.

The Queen's bloodstock adviser John Warren said: "I think everyone involved is absolutely thrilled - all of her majesty's team, and obviously Andrew and his team.

"Throughout the conversations the Queen was saying how delighted she is to produce a two-year-old winner at Royal Ascot."