Four-time Cox Plate winner Winx has got through a final tune-up unscathed ahead of her return to racing in the Group Two Apollo Stakes at Randwick on Saturday.

Preparing for her final campaign before retirement, the seven-year-old mare gave a glimpse of her trademark speed as she galloped down the Rosehill straight on Thursday morning.

But the final training gallop almost didn't go ahead, with trainer Chris Waller harbouring concerns about a nearby fire.

"There was a fire at Rosehill (and) a bit of smoke around," he said.

"I was just constantly thinking 'do we bring her out, or do we abort this morning's media call?'.

"But fortunately there was a little bit of a break in the smoke and we got her to breeze up the straight perfectly."

Champion jockey Hugh Bowman gave the mighty mare his tick of approval, saying she's made significant strides in her fitness over the past month.

"She's looking great in my eye," Bowman said

"She looks excellent in the coat and has got a real glow in her eye, as does Chris, which is exciting."

Bowman insisted it was business as usual despite Winx nearing the end of her unprecedented career.

"I always look at it as a stepping stone towards the rest of her preparation," he said.

"I guess there is that little element of unknown because she hasn't raced since the Cox Plate.

"But all signs that she's shown us are that she's ready to go."

Winx is aiming to extend her winning streak to 30 and claim a third Apollo Stakes after winning the 1400m race in 2016 and 2017.

She'll have to get past seven rivals to do it, five of whom come from Waller's yard