Madame Chiang finished with a flourish after being reluctant to go in the stalls to lift the Qipco British Champions Fillies & Mares Stakes at Ascot.
Jim Crowley worked hard on David Simcock's mud-loving three-year-old, who ran as straight as an arrow to profit from the erratic path taken by Chicquita, who had gained a clear-cut advantage over a furlong out.
Leading inside the last 100 yards, Madame Chiang (12-1) went on to win by two lengths from Silk Sari, who came from a long way back to claim the runner-up spot. The wayward Chicquita was third.
Crowley said: "On that ground we were making heavy weather of it - everyone was. I got a lovely run through and she was very game. She relished the ground and David Simcock was always confident she'd go on it. It worked out great."
Simcock added: "I was delighted Jim never panicked on her - that's her style of racing. It's also great for Kirsten (Rausing, owner). It was the best run of her career. It's very, very special."
Luca Cumani was deeply satisfied by the performance of Silk Sari.
He said: "I really thought we were in for a shockingly bad run. But once she got into the straight she was full of running. Had it been a longer straight she might have even got there. She ran a fantastic race."
Connections of Ballydoyle challenger Chicquita were philosophical in defeat in light of the filly's chequered past.
Jockey Joseph O'Brien said: "She has a tendency to do that in her races. She came there to win, but that's just the way she is, I'm afraid."
