A Shin Hikari, the heavy favorite for the Group 1 Prince of Wales’s Stakes on Wednesday at Royal Ascot, proved a major disappointment, but Lady Aurelia most certainly did not in the Queen Mary Stakes. The Wesley Ward-trained 2-year-old filly turned in what must have been one of the more memorable performances in the modern history of Royal Ascot, winning the Group 2 Queen Mary Stakes by seven lengths. That huge margin came in a race just five furlongs long, and Lady Aurelia stunned her rivals with a devastating turn of foot to accompany dominant speed. “It was breathtaking from the top,” said winning rider Frankie Dettori. “For a winner to spring seven lengths at Royal Ascot is unbelievable.” Lady Aurelia had won like a star first out at Keeneland but now was being asked to go down a straight course on soft turf that might well have blunted her speed. Instead, she broke like a rocket but was putty in Dettori’s hands, going well clear of her rivals while under total control. A furlong and a half from home, Dettori asked Lady Aurelia for run, and in an instant she opened a huge margin on 16 struggling pursuers. She was geared down late and still ran five furlongs in a strong 1:00.14.  “When I got to the furlong-and-a-half and I asked her to go, she found another gear. I was completely shocked,” Dettori said. Ward won his eighth Royal Ascot race and the Queen Mary for the third time, following Jealous Again in 2009 and Acapulco last year. Ward said Lady Aurelia will remain overseas and be pointed at the Molecomb Stakes next month at Goodwood or the Prix Morny at Deauville in August. Lady Aurelia is by Scat Daddy and out of D’Wildcat Speed. She was bred by Stonestreet Stable, which owns her in partnership with George Bolton and Peter Breidel. Upset in Prince of Wales’s My Dream Boat scored a major upset in the Prince of Wales’s Stakes, just touching off the filly Found as the heavily favored Japanese runner A Shin Hikari led and faded to last in a six-horse field. A Shin Hikari had beaten My Dream Boat by 14 1/2 lengths in the Prix d’Ispahan over soft ground last month in France, but My Dream Boat, making just his second Group 1 start, ran much better Wednesday, while the favorite failed to come close to his best. Second from last while saving ground around right-handed turns over Adam Kirby, My Dream Boat came out for the stretch run and, despite drifting out, came home slightly better than Found, who had made what looked like a winning move under Ryan Moore. “He got a little bit trapped back in the field last time but got a nice rhythm today,” said winning trainer Clive Cox. A Shin Hikari showed the way but had no response when the pace quickened in the final quarter-mile. He was said by his connections to have come out of the race without incident. Miss Temple City fourth as Usherette impresses The ascendant 4-year-old filly Usherette, one of three winners Wednesday for Godolphin, was much the best in the Group 2 Duke of Cambridge Stakes. Miss Temple City, the American horse trained by Graham Motion, made a solid rally from the back to nab fourth in a creditable performance. Trained by Andre Fabre, Usherette beat Furia Cruzada by 2 1/4 lengths, giving Mickael Barzalona his first Royal Ascot winner. She has now won six of seven starts and will be pointed to a Group 1 race, perhaps the Falmouth Stakes.