Joyeuse enjoyed the descent into Listed company to convincingly land the EBF Stallions Stakes at Haydock Park.
Lady Cecil's underrated filly (3-1 favourite) banished memories of her chastening 1000 Guineas run, in which she finished 11th, to determinedly account for Irish challenger Gathering Power.
Joyeuse, ridden by Ryan Moore, galloped earnestly through a nice gap between German hope Gracia Directa and Gathering Power halfway along the home straight to collect by a length and a quarter.
Perfect Blessings finished third, but she was soundly beaten by another four and a half lengths.
Lady Cecil said: "She's by a sprinter out of a sprinter, so it's no surprise six furlongs suits her well.
"I'm delighted for everyone back at Warren Place as she's a bit of a quirky customer and takes a bit of handling.
"We'll speak to Teddy (Grimthorpe, racing manager for owner Khalid Abdullah) and the Prince about plans, but we might stick at this sort of trip, and this ground seems to suit her well."
Moore went on to complete a brace when 11-10 favourite Wrangler, trained by William Haggas, got up late in the day in the Follow The Scoop6 At totepoolliveinfo.com Handicap.
Maureen Haggas, the trainer's wife, said: "He loves that ground and I think he's the only person whose looked happy at Haydock all day! He's had his ears pricked since the moment he arrived and he's really enjoyed himself. I'm sure he'll have learnt plenty today and that ground is the key to him."
Trainer Alan King and jockey Fergus Sweeney combined to take the Betfred Mobile Casino Silver Bowl with 7-1 shot Chatez as the long-elusive Scoop6 was finally landed.
Sweeney said: "We love this horse and he's never finished out of the first three. He's done everything right today and hopefully he might get in the Britannia (at Royal Ascot) now."
