Too Darn Discreet will attempt to follow the lead of Zardozi who won the Edward Manifold – Crown Oaks double at Flemington 12 months ago.
Ballarat trainer says he would not change anything as Too Darn Discreet looks to extend her winning sequence at Flemington.
The Group 1 Crown Oaks (2500m) on Thursday will be the daughter of Too Darn Hot's fourth win on end if successful.
Too Darn Discreet started the ball rolling with a maiden win at Sandown, progressing to the Edward Manifold Stakes (1600m) at Flemington then to the Ethereal Stakes (2000m) at Caulfield.
"I'll tell you after Thursday whether it has been the perfect prep, but I wouldn't change anything," O'Sullivan said.
"I'm glad we didn't go down on Saturday for the Wakeful because she'd had the run over 2000 metres before that.
"She galloped really well on Saturday morning, had a top up gallop on Tuesday, she's got a good draw, barrier three, and she should get a good economical run from there.
"She's ready to go."
The 2500 metres on Thursday is unchartered waters, as it is for the filly's 13 rivals, but O'Sullivan is confident she will stretch out.
O'Sullivan is also banking on a return to Flemington suiting the filly.
"She was very tough at the end of 2000 metres in the Ethereal, so I've got to be guided by that," O'Sullivan said.
"I think she will be better suited on the bigger, flatter track at Flemington, and I think she looked better in the Edward Manifold than what she did at Caulfield, so you have to back yourself.
"She's a very tough filly and we've done the work for her to run out the trip, and I think we have done that, so the proof will be on Thursday."
Too Darn Discreet holds a nomination in the Group 1 Thousand Guineas (1600m) at Caulfield on Saturday week, but O'Sullivan said the filly would be in the paddock by the time that race is run.
"I put her in as a back-up, just in case there was a simple thing like she pulls a shoe off and gets a foot abscess, or something goes wrong, and you haven't put yourself in there," O'Sullivan said.
"You're then in the paddock instead of going to a race that would have been an option, but it was purely as a back-up.
"She'll be in the paddock after the weekend.
"We'll give her a few days to let down and as she's owned in South Australia we'll prepare her for Adelaide and the Australasian Oaks."
