Melbourne Cup winner Michelle Payne will realise another dream when she gets the chance to compete in her first Cox Plate.

Payne shot to international prominence two years ago when she became the first female jockey to win the Melbourne Cup on Prince Of Penzance at Flemington.

On Saturday Payne will be legged aboard the Jane Chapple-Hyam-trained Kaspersky in another of Australia's most important races - the $3 million Cox Plate at Moonee Valley.

Payne rode Kaspersky to fifth placing in the Queen Anne Stakes at the famous Royal Ascot meeting in England in June.

"The Cox Plate is one of my favourite races from growing up," Payne said.

"I haven't missed a year, so to be out there on Saturday would be really special."

Champion Winx is the $1.15 favourite to win her third Cox Plate, with rival connections realistic about the task ahead.

Payne won the Melbourne Cup on a $101 chance and English horse Kaspersky is at $81 in the field of nine.

"I don't know if I would be the most popular person in Australia if we happened to beat Winx," Payne said.

"But I don't know whether we have to worry too much about that.

"You can only do your best. We'll go out there and treat it like any other race and give it our best shot and see what happens.

"It would be pretty special (to win).

"It's right up there with the Melbourne Cup. Obviously it's such a unique race because the committee only let in certain horses that they think are eligible to compete in it. That's, I think, very special because I don't know whether there's too many races in the world that have that.

"If we were able to be successful would be an unbelievable dream. But just to be out there is going to be great."

Payne also holds a trainers' licence in Victoria and has scarcely ridden in races this season.

She rode her first winner for 2017/18 at Stawell on Monday on a horse she also trains, wearing the same colours Kaspersky carries.

Illness forced her to miss riding Kaspersky when he ran 16th in the Toorak Handicap, but she rode him at trackwork at Moonee Valley on Tuesday and said the horse was in great order.

Payne's brother Patrick won the 2002 Cox Plate on champion Northerly.

"I actually took the day off racing in the country that day because I didn't want to miss watching Patrick on Northerly," Payne said.

"To be there with my family, and all my school friends were out with a picnic on the lawn, it was a very special day and something we've always remembered."