Filling the void left by Minding is starting to look like an easy task for trainer Aidan O'Brien after Winter registered a fourth top-level success with victory in the Group One Nassau Stakes at Goodwood.

Having claimed the race 12 months ago with the now-retired Minding, O'Brien landed the prize again thanks to another equally talented filly.

Soft ground denied Churchill the chance to run in the Sussex Stakes 24 hours earlier, but O'Brien's frustrations turned to joy on Thursday (Friday AEST) as this year's English and Irish 1000 Guineas winner took the step up to a mile and a quarter (2000m) in her stride.

Travelling just behind the early pace set by eventual third Sobetsu, the 10-11 favourite was sent on to win her race by Ryan Moore just outside the final furlong (200m).

Any doubts regarding her stamina were emphatically erased, with Winter pulling comfortably clear.

"We are over the moon," O'Brien said.

"Racing in that ground was like racing on National Hunt ground and that is a different level of fitness you need for that.

"It was a bit of risk running her, but we had it in our head that she is a big, powerful mare with big feet. Ryan minded her and did a great job with her.

"She is a filly to look forward to and she should be ready for the second half of the season now. Getting a mile and a quarter well leaves an awful lot of options open for her. She might even get further.

Winter was cut to 8-1 from 12-1 for the Juddmonte International at York by RaceBets, with Paddy Power going 3-1 from 8-1 for the Irish Champion Stakes.