Ryan Moore broke the post-war record for winners at Royal Ascot when Aloft gave him a ninth winner of the week in the concluding Queen's Vase.

But the crack English jockey was on the receiving end of a master-class from Christophe Soumillon in the feature race on day four.

Riding Ervedya for the Aga Khan, Soumillion threaded his way through traffic to deliver the French-trained filly with perfect timing in the 375,000 Coronation Stakes for fillies over 1600m.

Soumillon pounced just as Moore was entertaining thoughts of victory aboard Found, who went to the front 300 metres from home.

Yet having reeled the leader in, Soumillion had to contend with the even later flourish of Kevin Manning aboard Lucida.

It was a pulsating finish as Ervedya prevailed by a neck from Found, with Lucida a half-length back in third place.

Miss Temple City, the US challenger, acquitted herself with credit in taking fourth place.

Soumillon has long been among the finest jockeys in Europe but this was just his second Royal Ascot winner -- and his first at Ascot itself.

His previous victory aboard Valixir -- also in the Aga Khan's silks -- was gained at York in 2006, when Ascot racecourse was being redeveloped.

"I was lucky to find a gap through them," an elated Soumillon said.

"I knew Found was the horse to beat and so I stayed behind her. Maybe that's why we won. If I had challenged down the outside she might have found the (race) distance a bit too far for her."

At least Found ran up to her best under Moore, who had high hopes of winning the newly-inaugurated STG375,000 ($A763,000) Commonwealth Cup aboard Hootenanny.

But the American speedball failed to fire over the 1200-metre journey.

The race was won by an emerging star in Muhaarar, who exploded under jockey Dane O'Neill to scorch clear of Limato to win by 3 lengths.

Owned by Sheikh Hamdan Al Maktoum, Muhaarar is trained by Charlie Hills, who saddled Dutch Connection to win the Jersey Stakes on Wednesday.

"This is probably the best horse I have trained," said Hills, who also saddled the fourth-placed finisher, Salt Island.

On another warm day at the royal racecourse, two jockeys to whom Royal Ascot had been unkind this year experienced better fortunes.

Jamie Spencer, so unfortunate to be denied victory on The Grey Gatsby in the Prince Of Wales's Stakes on Wednesday, found consolation aboard Balios in the King Edward VII Stakes.

Spencer brought the David Simcock-trained horse through from last place to collar Mr Singh after the favourite, Stravagante, had injured himself during the race.

Stravagante is trained by Sir Michael Stoute, who suffered similar misfortune when his Capal Path, owned by Her Majesty the Queen of England, was injured in a race on Thursday.

Having stayed overnight at a local veterinary clinic, Capel Path was moved to Newmarket on Friday for further examination.

But Stoute's misfortunes were later compounded when Yarrow, his runner in the last race, was quickly eased out of the contest by jockey Pat Smullen.

Although Richard Hughes had ridden some fancied horses throughout the week, the jockey had yet to visit the winner's enclosure at his last Royal Ascot before his retirement.

That changed when Hughes rode two winners. Appropriately, the first of them came in the Albany Stakes aboard Illuminate, who is trained by Richard Hannon.

It was with the support of Hannon's father, also Richard, that Hughes rose to the top of his profession.

"He is going to leave a big hole," an emotional Hannon said of Hughes, who is also his brother-in-law.