One Master will not take her chance in the Breeders' Cup Mile at Keeneland after being scratched from Saturday showpiece.

The seven-year-old mare, trained by William Haggas, was found to be set-fast when she was exercised on Thursday.

“She got a bit set-fast on her first morning out. Her muscle enzymes are too high,” said the trainer, speaking from home in Newmarket.

“I’m disappointed, but very pleased that they are not risking her at all.”

One Master made history at ParisLongchamp last month by becoming the first horse to win the Prix de la Foret three times.

She was also a close third to Glen Shiel in the British Champions Sprint Stakes at Ascot, on her what was her seventh race of the season. She is likley to be retired now.

Her absence from the Mile sees first reserve Order Of Australia, trained by Aidan O'Brien gain a last-minute place in the field. Christophe Soumillon rides.

READ SEAN CLANCY'S RACE-BY-RACE BREEDERS' CUP PREVIEW IN THE IRISH FIELD THIS WEEKEND