Big Orange won a thrilling three-way finish to take the Goodwood Cup.
Jockey Jamie Spencer took Michael Bell's four-year-old to victory over 9-2 favourite Quest For More by a neck, with a short head back to Gold Cup winner Trip To Paris.
Jockeys wore black armbands in memory of the late Sir Peter O'Sullevan.
Three-time Champion jockey Richard Hughes won his first race of the festival, on Gibeon in the Land Rover Stakes.
The 42-year-old will retire on Saturday to begin a training career.
Gibeon, a 11-1 shot, just held off the fast finish of 4-1 favourite Keble by a neck.
"I'm glad I've got one, I can retire a happy man now," said Hughes.
Elsewhere Shalaa, ridden by Frankie Dettori coasted home to beat Tasleet by two and three-quarter lengths in the Richmond Stakes.