Go Indy Go will run over 2040 metres at Moonee Valley on Saturday - but not in the race her trainer had originally hoped.

After she won the Champagne Stakes in the autumn, Leon Macdonald and his training partner Andrew Gluyas turned their thoughts to the Cox Plate as a lead-up to the VRC Oaks.

Things have not quite gone to plan this spring and the filly heads to the Vase at Moonee Valley instead of the weight-for-age championship.

Go Indy Go put in the worst run of her short career first-up in the Danehill Stakes, finishing last of the 15 runners.

A full veterinary examination failed to detect any problem and the filly improved to run third in the Thousand Guineas Prelude before her 3-1/4 lengths seventh in the Group One.

"The way the Thousand Guineas was run she really didn't have a chance to catch them," Macdonald said.

"I'm happy with her. She is still a little bit lighter than I would like but she is fit and well and came through the Guineas in good order.

"She goes to the Vase. It will be the test whether she goes on to the Oaks.

"I think the extra distance will suit her. She is a very relaxed filly and has the right temperament to run over longer."

Last year's Cox Plate winning jockey Chad Schofield will be reunited with Go Indy Go in the Vase.

He had been prepared to get down to the filly's 47kg weight in the Cox Plate but in her absence he will ride three-year-old Sweynesse at 49.5kg if the Godolphin colt starts in the race.

Go Indy Go is at $13 for the Oaks (2500m) on November 6 with Crafty the $3.50 favourite after her second to her Robert Smerdon-trained stablemate Fontein Ruby in Saturday's Caulfield Classic (2000m).

Fontein Ruby is at $8 with another Smerdon-trained filly Lumosty at $9.