Big Orange held off a strong late charge from Order Of St George to win a pulsating Royal Ascot Gold Cup.
James Doyle steered the Michael Bell-trained Big Orange to a thrilling victory by a short head to deny Order Of St George back-to-back victories in the prestigious Group One race.
Jockey Doyle only took the ride in the absence of the injured Frankie Dettori this week and made the most of his unexpected opportunity on Ladies Day.
The 5-1 shot Big Orange turned for home at the front and passed a huge stamina test over two and a half miles to stay on strongly and edge out the fast-finishing Order Of St George, with Harbour Law third.
Aidan O'Brien celebrated a seventh win in 11 seasons when Order Of St George came home last year, but the finishing line came just too soon for the 5-6 favourite under Ryan Moore as Big Orange held on.
Doyle told ITV Racing: "Frankie is a real star. He phoned me the other day and I was speaking to him for about 20 minutes, he was not giving me orders, but just instructions.
"He said don't interfere with him, he knows what speed he wants to go at, so just sit as a passenger. I had Frankie's voice in my head, so I eased him out and let him go from the front and the rest was history."