Trainer Chris Waller and jockey Hugh Bowman are keeping their cool ahead of Winx's return at Randwick where temperatures are expected to reach record highs for February.

The Australian Turf Club will have measures in place on Saturday for the comfort of racegoers as well as the horses as the mercury nudges 40 degrees in Sydney.

Waller said he was not concerned about the heat affecting Winx or any other horse given the protocols in place.

"They have good racing policies in the heat, so the horses aren't exposed to the extreme of the sun for too long," Waller said.

"They have a short parade. They're basically only out on the track for about 10 minutes, and then back in the stalls.

"They can then again have a shower and ice baths.

"There's plenty of thought that goes into the day. It's not perfect but very safe."

One thing that is perfect ahead of the Group Two Apollo Stakes is the star attraction who was given a final work-out by race jockey Hugh Bowman on Thursday morning.

The 1400m-race will be Winx's first since her Cox Plate defence in October which cemented her standing as the world's best horse on turf.

She is at $1.12 to extend her winning streak to 14.

"I don't feel pressure but more a high level of responsibility," Bowman said.

"It's up to her to perform and I just try to keep it simple."

Waller is also relaxed.

"It's always a little bit of a concern where she's at," he said.

"But she hasn't got to this status by fluking wins. Simply she's a very good horse and that gives us confidence for Saturday."

Winx will have 11 opponents trying to end the winning sequence including Hartnell, Australia's second best horse at equal eighth in the 2016 world rankings.

He is at $9.50 and the only other horse under double figures.

When they last met, Winx beat Hartnell by eight lengths in the Cox Plate before he went on to run third in the Melbourne Cup.

"I couldn't be happier with his attitude and his fitness level," Godolphin trainer John O'Shea said.

"We're looking forward to a good, positive day. It's likely that the track will be rain affected which will be good for him.

"We're really looking forward to him getting started off on Saturday and to the rest of the campaign."