Ms Hales, 38, is unlikely to be overawed by the occasion - she's been in front of big racing crowds before, including Saturday at Flemington with rising stable star Preferment after the 3-year-old won Australia's oldest race, the Victoria Derby, despite not winning in six previous races.
"Saturday was pretty big," she told Hawke's Bay Today from Melbourne yesterday..
Looking to today's big race, she reckons Japanese entry Admire Rakti, the topweight and Caulfield Cup winner, will be toughest to beat.
She says the three Waller stable horses are all in with a chance, but her mum plumps for Who Shot The Barman, because it's owned by dairy farming family friends from Wanganui.
Despite the minimal number of New Zealand and even Australian horses in what was once effectively a Bledisloe Cup of endurance for the best transtasman stayers, it's still expected to stop the nation today.
Kiwi punters are expected to bet more than $10 million on the cup day.