He has won Sydney's two richest races of the spring, now Chris Waller has set his sights on the biggest prize money offering in Melbourne.

Racing purists turn away because the sport might be about to usher in a new grand slam.

Historically, the Melbourne and Caulfield Cups, Cox Plate and Golden Slipper have been revered as Australian racing's 'big four' and that won't change anytime soon.

But trainer Chris Waller is on the verge of a trifecta of spring wins that symbolises the changing face of the industry.

After preparing a record four Group One winners on a single afternoon last month, Waller has continued to dazzle this carnival season.

He won Australia's richest race, the $14 million Everest, with Yes Yes Yes and on Saturday added the third richest, the $7.5 million Golden Eagle courtesy of Kolding.

The $8 million Melbourne Cup is the missing link and if Waller can win it with Finche or Youngstar, he will have a clean sweep of the country's biggest prizemoney purses.

Waller's duo both contested the race 12 months ago finishing fourth and sixth respectively.

He is leaning towards Finche as his best chance for a maiden Cup win and so are punters with the horse backed into equal $8 favouritism on Monday.

"Finche rates a little bit higher than Youngstar this year and he did run fourth in the race last year when running particularly well after having to do quite a bit of work in the early stages from a wide draw," Waller said.

"Fortunately, he has the luxury of gate four this year so should have a more economical run."

While Finche has raced consistently well in four starts this campaign, including a victory in the Kingston Town Stakes in Sydney, Youngstar's form has been mixed.

But she did improve off the back of a significant distance rise last start and Waller says she is bigger and stronger.

"This time last year Youngstar was the horse on everybody's lips and unfortunately her form is not quite as good as it was going into the race this time last year," Waller said.

"But in saying that, she has run in the right races in terms of building her stamina and I am happy with her from that perspective."

Waller's pair are among 12 Australian-trained horses in the field of 24 and both will be ridden by local jockeys, Kerrin Mcevoy on Finche and Tommy Berry aboard Youngstar.