Stradivarius won the Goodwood Cup for a record fourth time under jockey Frankie Dettori on Tuesday.
The six-year-old winner, trained by John Gosden, was conceding weight to some rivals and briefly looked short of room approaching the final furlong.
But Dettori stayed calm on the 4-7 favourite, and powered clear of runner-up Nayef Road (20-1) with Santiago (15-8) finishing third.
It was a joint record sixth career win in the race for the 49-year-old rider.
“Stradivarius looked like he was boxed in. It was a great performance under that weight. It was a big ask and he has a big heart,” said Gosden.
The Newmarket trainer had said before the race that this was “the greatest challenge” yet for Stradivarus, who carried 15lb more than the Irish Derby winner Santiago under weight-for-age rules.
But the horse, who won a third Gold Cup at Ascot last month, ran out a one-length winner and will now be aimed at the Prix Foy before a tilt at the Prix de l’Arc de Triomphe in France.
“What a horse, giving 15lb away. Everybody rode to beat me and he still gets out and wins. What can you say, he’s an amazing horse,” said Dettori.
The Italian was celebrating his second landmark in three days after winning a record third King George VI and Queen Elizabeth Stakes at Ascot with another six-year-old, Enable, on Saturday.
Glorious Goodwood’s first four days are taking place without spectators because of the coronavirus pandemic, with around 4,000 racegoers allowed in on Saturday’s final day as a pilot event for crowd returning to sport.
“Having two six-year-olds is a weighty responsibility, but this year we’ve had a sinister disease and it’s been nice to have old friends about,” added Gosden.