Chris Waller admits the build-up to Winx's bid for a Cox Plate treble will not match the intrigue of last year as rivals shy away from the challenge.

At Moonee Valley 12 months ago the rivalry between Winx and Godolphin's Hartnell was built up as a match-race before the champion cleared out to beat him by eight lengths.

"It was great last year. I think it was great for racing with Hartnell and a few internationals," Waller said.

The Cox Plate field is declared on Tuesday and there could be as few as a half dozen runners when Winx bids to extend her winning streak to 22.

English Godolphin trainer Charlie Appleby confirmed on Sunday Cranbourne Cup winner Folkswood would run while others likely are Caulfield Stakes winner Gailo Chop, Epsom Handicap winner Happy Clapper and three-year-old Royal Symphony, the unlucky beaten favourite in the Caulfield Guineas.

Waller said the composition of the field was the least of his concerns and he understood the reticence of rival trainers to test their horses against Winx.

After all, he said it was highly unlikely that he would pit a stablemate up against her on Saturday.

"It's not Winx's fault if they don't get a full field," he said.

"I've been a trainer long enough to know it was hard to beat Black Caviar and you like to find a race you think your horse can win.

"It's a privilege that other people think that way and I respect that getting beaten isn't easy. If there's other options to win it might be reason for taking another path."

Winx was taken to Moonee Valley last week for a solo gallop away from the limelight but is expected to be among the hustle and bustle of Breakfast with the Best at the track on Tuesday.

Waller offered no comfort to Winx's eventual opponents when he declared she was on track to match Kingston Town's Cox Plate three consecutive Cox Plate wins.

"Track conditions are no problem for her. Distance is no problem and neither is Moonee Valley," he said.

He emphasised the pressure he and his staff were under to ensure Winx was ready on race day and he is also preparing for the day she is beaten.

"With her every race is the Cox Plate," Waller said.

"It's so hard to explain the build-up and it's not through public expectations. It's not through media expectations. It's simply for us making sure we're doing our job to make sure the horse isn't let down.

"I don't want her defeat to be a man-made one. I want it to be when she's ready to step down from the throne."