MELBOURNE, Nov 3, 2025 (BSS/AFP) - Half Yours heads into Tuesday's Melbourne Cup as short-priced favourite ahead of Valiant King and Al Riffa, setting the scene for a woman jockey to win Australia's "race that stops a nation" for only the second time.

First run in 1861, the punishing 3,200-metre (two-mile) handicap at Flemington is regarded as the ultimate test of stamina and staying power.

In all those years, only one woman has tasted victory.

That was Michelle Payne, who famously steered 100-1 outsider Prince of Penzance to glory in 2015, propelling her into a household name with a movie, "Ride Like a Girl", made about her exploits.

Jamie Melham, who came third last year aboard Okita Soushi, has perhaps the best chance since to match the feat on five-year-old galloper Half Yours, trained by father-son duo Tony and Calvin McEvoy.

She rode the gelding to victory at the Group 1 Caulfield Cup last month -- the first woman to win that race in its 149-year history -- and will start from an ideal barrier eight.

"It was a beautiful ride she gave to Half Yours in the Caulfield Cup and it's much different to me riding a 100-1 shot in the Melbourne Cup," Payne told reporters.

"Riding the favourite, like she did in the Caulfield Cup, she took it all in her stride and gave him the perfect ride to win the race and also to prepare for a Melbourne Cup."

New Zealand's Maree Davey was the first woman jockey to saddle up at the Melbourne Cup in 1987. A record four women took part last year.

With Aus$10 million (US$6.5 million) at stake, the winner of the 24-strong field will bank Aus$4.5 million and instantly become famous in Australia, where the race is a cultural institution.

- 'Rain dance' -

This year there are three women jockeys with Rachel King on outsider Arapaho and Celine Gaudry entrusted with Geelong Cup winner Torranzino.

Working in Half Yours' favour is forecast rain and his light 53kg weight, with Calvin McEvoy saying: "Love it, bring it on. We're doing the rain dance.

"He absolutely loves the wet, this horse."

Stayer Al Riffa was an early equal favourite, elevated after previous frontrunner Sir Delius was ruled out after vet scans showed the English galloper at "heightened" risk of injury.

However, a horror barrier 19 draw saw the Joseph O'Brien-trained hope slip down the betting ladder.

But with ace jockey Mark Zahra at the reins, the six-year-old remains a serious contender after a dominant four-length win at the Irish St Leger over 2,800-metres in September.

O'Brien is a two-time Melbourne Cup winner with Rekindling (2017) and Twilight Payment (2020) and is excited despite Al Riffa being the top-weight horse at 59kg.

"He's a multiple Group 1 winner so he's going to carry a lot more weight, but he's going to carry it because he's a very high-class horse," O'Brien said.

Zahra rode Gold Trip to Melbourne Cup success in 2022 and repeated the feat on Without a Fight a year later.

He headlines several Melbourne Cup-winning jockeys back again, including 2020 champion Jye McNeil on the Chris Waller-trained Valiant King, whose prospects soared after drawing barrier 10.

The six-year-old gelding scored its biggest win to date at the Bart Cummings over 2,520m at Flemington last month, before a third behind Half Yours at the Caulfield Cup.

Craig Williams, who rode Vow And Declare to victory in 2019, will take the reins of joint-third favourite Buckaroo while Robbie Dolan, who won last year on rank outsider Knight's Choice, is on-board Royal Supremacy.