Franconia has been pulled out of Thursday's Tattersalls Musidora Stakes at York following a bad scope.
Franconia impressed when finishing second on her debut at Chelmsford City last year before recording a victory at Newbury last month.
John Gosden's charge was at the top of the market for Thursday's contest but will not line up after the trainer confirmed she was not in shape to race.
Graham Lee was due to take to the saddle with Frankie Dettori named to ride stablemate Ricetta instead in the race as Gosden explained the decision.
He said: “I scoped Franconia on Tuesday morning after she gave a cough at exercise and we got the results back this morning which showed she had a mucus issue so we had to take her out.
“I switched Frankie on to Ricetta yesterday when I thought it was unlikely that Franconia could run.”
A field of eight is now set to line up for the Musidora Stakes, including Ricetta and Lake Lucerne for Gosden, while Roger Charlton's Pocket Square and the Godolphin-owned Dubai Love are also in the mix.
