Jamie Melham on Half Yours only second woman to win Melbourne Cup
The five-year-old gelding pulled clear in the final stretch on a soft track to outpace Goodie Two Shoes and Middle Earth by 1.5 lengths in the energy-sapping 3,200-metre (two-mile) handicap at Flemington.
"Oh my God, this is what we do it for," said Melham, who came third last year aboard Okita Soushi and won the Caulfield Cup on the all-Australian Half Yours in her last ride.
"This is why we get up out of bed every morning at 4am, it's tough, it's not all glorious and perfect as everyone can see sometimes.
"I've had an amazing year," she added. "Got married, had some really great days on the track, but nothing ever, ever compares to this feeling right now I'm feeling."
She joined Michelle Payne, who famously steered 100-1 outsider Prince of Penzance to glory in 2015, as the only women to win the race.
First run in 1861, 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 and three this year.
"Welcome to the club," Payne, who was commentating, told Melham.
"We have so many young girls coming into our industry and to see her win the Caulfield and Melbourne Cup double, is just so fitting. She is such a hard worker."
Trained by father-son duo Tony and Calvin McEvoy, Half Yours was an early favourite but French galloper Presage Nocturne took over at the head of the market 30 minutes before race start at $7.00.
'An amazing horse'
Half Yours was second favourite at $8.00 ahead of Irish raider Al Riffa, who finished seventh, in cool and overcast conditions for the 24-strong field.
Presage Nocturne finished well out of the placings.
"What a horse. He's continued to raise the bar. I've got no words, what an amazing horse," co-trainer Calvin McEvoy said.
A cultural institution in Australia, the Melbourne Cup has been run on the first Tuesday of November since 1876 and is considered so important it is a public holiday in its host state of Victoria.
Held in front of a bumper crowd, drinking and socialising took priority over racing for many despite the miserable weather, with the sound of popping champagne corks accompanying the thundering of hooves.
Breaking from barrier eight, Half Yours settled in the middle of the pack behind early pacesetter Land Legend.
With 1,000m to go, Land Legend was eight lengths ahead but tired and was slowly reeled in down the home stretch where Half Yours kicked clear.