Kieren Fallon's renaissance has continued at York with his victory on Madame Chiang in the Musidora Stakes, a key trial for the Oaks.
David Simcock trains the unbeaten filly for Kirsten Rausing and while connections did not fully commit her to the next month's Classic at Epsom, it is believed she will take her chance if the ground is not too fast.
Winner of a Yarmouth maiden on her only start at two, the Archipenko filly was settled at the back of the pack by Fallon, who recently struck in the 2000 Guineas and has a leading Derby chance in True Story.
Lily Rules took over two furlongs and appeared set for victory, but Fallon was only beginning to wind up his mount and having joined the leader, she knuckled down to win by a length and a quarter at 8-1.
"I had to work hard on her, but we did go quite quick," Fallon said.
"She's a beautiful big filly and David had a lot of confidence in her.
"She didn't do a tap in front and I just had to give her a couple of flicks to keep her going."
Simcock said the French Oaks was also under consideration.
"I don't think it would be fair to her to step foot on firm ground at this stage of her career. Cut in the ground is very important to her," Simcock said.
"If it came up with cut in the ground it (Epsom) would certainly be an option. France is an option as well."