William Buick believes The Fugue can give him a genuine opportunity of a first Epsom Classic victory in next Friday's Investec Oaks.
John Gosden's stable jockey has won the last two St Legers for his boss, as well as Group Ones around the world, and will also have a Derby ride in Thought Worthy.
But The Fugue, who is the joint-favourite for the Oaks with some bookmakers, is his main hope on the Surrey cambers.
Andrew Lloyd-Webber's filly was fourth on her reappearance in the 1000 Guineas before Buick helped her take York's Musidora Stakes in impressive fashion.
"The Fugue is a lovely filly - she won the Musidora very easily - she has the quality to go very close," he said.
"She has a realistic chance of winning the Oaks which is very exciting. That is the good thing about her - she has a great temperament.
"She was great before the race at York and travelled beautifully in it. She has done everything right and she strikes me as a filly who will go round Epsom, though you never really know until the day. I feel she has all the right attributes."
Buick won the Fairway Stakes on Thought Worthy last weekend and Gosden has primed the colt for a quick turnaround.
"Thought Worthy did well to win at Newmarket over his minimum trip," the jockey said.
"He looked beat but appreciated the rising ground and will definitely excel over a mile and a half (in the Derby).
"There is plenty of improvement in him but whether he will handle the track I am not sure. He deserves his chance."
Completing Buick's full book in the Group Ones at the Derby meeting is Masked Marvel in the Diamond Jubilee Coronation Cup.
Last year's Leger hero was disappointing on his reappearance in the Jockey Club Stakes but shaped well under Buick in a racecourse gallop at Epsom as part of the Breakfast With The Stars morning.
He finished just ahead of Joviality (Robert Havlin), who is bound for the Princess Elizabeth Stakes, and a lead horse.
"Masked Marvel went well this morning - the ground was too soft for him at Newmarket. The way he went this morning, you would have to be hopeful at Epsom," Buick said.