As Via Sistina did last year, the Champions Stakes is the mare's second Grand Final in the space of two weeks having won the Cox Plate (2040m) at Moonee Valley on October 25.
Waller said the stable had kept Via Sistina up to the mark since the Cox Plate victory without over-training her.
"She's a very fit horse and runs well fresh, whether it's the first run of the prep, or the last," he said.
"We haven't complicated things, we've kept her happy, making sure she hasn't put on weight, and the stiffer the competition the better.
"We've seen that this preparation with the only real test coming in the Cox Plate when she came out on top.
"Her two runs prior to that weren't as stiff because they went at a very sedate tempo.
"Hopefully there's a bit of speed on. Flemington, over 2000 metres, they get rolling and it should play into her hands."
While Via Sistina holds an entry in both the Hong Kong Cup (2000m) and the Hong Kong Vase (2400m) at the international meeting in Hong Kong next month, Waller said it was unlikely the mare would travel.
"I haven't spoken to the (Yulong) team about that yet, and if they say we should be going, for various reasons, then we go," Waller said.
"But if not and we're fully concentrating on the autumn, it's better that she has a break."
Waller will also saddle Kovalica in Saturday's race, and while not expecting a surprise win, the trainer does expect the gelding to run well.
"He is going OK and his last run, he finished third behind Lindermann who is the form horse in Sydney at the moment," Waller said.
"He is fourth up, he's getting out to 2000 metres for the first time this prep.
"Often you see fresh legs during Cup week can have an effect and that's what we're banking on."