By Racinguk.com staff
Formerly with David Simcock, the five-year-old has improved steadily all year, winning a Group Three at Haydock, a Group Two at Deauville and then the Group One Prix Vermeille at Chantilly.
She beat Journey, winner of this race 12 months ago, in the Vermeille and will renew rivalry with John Gosden's filly at Ascot.
Graffard had been weighing up supplementing Bateel for the Prix de l'Arc de Triomphe but decided to keep her fresh for this weekend.
However, the French trainer admitted he would be more confident if the ground was on the soft side.
"All is fine ahead of Saturday and we're looking forward to it," he said.Bateel is a best-priced 9-2 with Paddy Power and Betfair for Saturday (PA)
"Obviously the softer the ground, the better it will be for her, but only because we know she handles it so well and some of the others might not.
"But she's a top-class filly and she has won on good ground this season."
The going at the Berkshire course is Good, Good to Soft in places, following 4mm of rain during the past 24 hours to 4pm on Wednesday. Heavy rain and winds of up to 49mph are forecast for Ascot on Saturday.