There was a Stewards' Inquiry after the event into an incident involving the winner who, when finding a gap in the field just over a furlong out, bumped into Pearl Away while dashing clear.
The race results were upheld by the Inquiry and Zagora was awarded the win by half a length from Bikini Babe, with fourth place Rumoush a further three-quarters of a length behind.
"We should have won by five lengths," said winning jockey Ioritz Mendizabal.
Mendizabal also said, "I was never really worried because she has so much speed but we didn't have any run until 200 metres out. Finally we won with plenty in hand and today I had to rely on her brilliant acceleration."
Though putting on a good finish, Bikini Babe never really challenged Zagora once she broke clear, while Richard Hills and his mount Rumoush held a small lead midway up the straight before but did not increase the speed.
Rumoush's trainer Marcus Tregoning said, "She is a real galloper and wants a longer distance but we were a little disappointed today.
"I don't want to make any plans until I see how the filly comes out of the race."
Hills added, "We had every chance but she was disappointing. It was an even gallop but she needs the longer trip."