Melbourne Cup-winning jockey Michelle Payne felt fate was on her side as soon as her brother Stevie drew barrier one for Prince of Penzance.

Stevie, one of the horse's strappers, wanted the number one barrier and got it at the draw on Saturday night.

"I thought this can't be true, he hasn't picked up number one," Payne said on Wednesday.

"From that moment I was like 'this is fate'."

Payne, the youngest of 10 children, felt calm and relaxed leading up to her becoming the first female jockey to win a Melbourne Cup.

She even predicted to Ballarat trainer Darren Weir and her family that the $101 outsider could win the Cup.

"It just sounds crazy to even say that before the greatest race in Australia and nearly the world," she told reporters.

"It's a dream come true and it's an absolute fairytale."

Prince of Penzance managing owner Sandy McGregor bought the horse after he was passed in for $50,000 at a New Zealand sale.

He retained 25 per cent, sold another quarter to John Richards, three Queensland men hold 15 per cent together and 35 per cent is held by about 20 people in two syndicates.

The owners celebrated in a Melbourne pub on Tuesday night.

"It was like true believers in there last night," McGregor said.

McGregor was also amazed when Stevie Payne drew barrier one.

"I said to Weiry: 'These Europeans are going to go home scratching their head I reckon. They pay a million dollars for a horse to come out and a little boy with Down syndrome turns up and pulls barrier one from underneath them'."