Champion Winx has returned to Chris Waller's stables to prepare for a third straight Cox Plate.

After winning the Queen Elizabeth Stakes at Randwick in April, Winx was sent for a break and Waller said she looked as if she had filled out.

The rising six-year-old completed four weeks pre-training on Sunday in preparation for a return to full training.

"I am very happy with the way she has returned from her winter break," Waller said.

"She appears as to have filled out a little and this is backed up by the scales, weighing 534 kg which is up about 5 kg at the same stage of her previous preparation."

Waller says he would like to get the next two weeks of training under way before locking in a definite program.

The Group Two Warwick Stakes (1400m) at Randwick on August 19 would be the ideal starting point to continue her unbeaten run which stands at 17.

"Naturally the spring program generally defines itself leading towards the Cox Plate and my intentions will be no different, spacing her races throughout to get her there in the best condition possible," Waller said.

"Obviously my staff, owners, Hugh Bowman and I, we are excited by her return."