The Aidan O’Brien stable would be as surprised as the rest of the racing world if  Rostropovich, pictured, pulled off an upset win over Winx in Saturday’s Group 1 Cox Plate.

The Australian TAB has Rostropovich at $31 in its latest Cox Plate market while champion racemare is a $1.20 favourite to notch her fourth win in Th Valley showpiece. O’Brien’s representative TJ Comerford said it was unlikely Winx would be beaten in the Cox Plate.

“I don’t think she is vulnerable bar she only a bad day herself, but she hasn’t had one of those in 28 straight runs and I doubt she’s going to have one here,” Comerford said.

“I’m not saying I’d be disappointed if he beat Winx, but I probably would be a bit surprised.”

O’Brien won the 2014 Cox Plate with Adelaide and ran third to Winx in 2015 but the camp has always said the Melbourne Cup was the main aim for Rostropovich, who was runner-up to Latrobe in the Irish Derby in June and won a Group III race at Leopardstown at his last run in September.