With the Thousand Guineas a spring goal for Ariaz, trainer Robbie Griffiths has worked backwards from that date to determine a starting point for the filly.

She gets her program underway at Moonee Valley on Saturday in the Cleanaway Plate over 1200m.

But Griffiths' confidence has been dented by a wide barrier and the likelihood of a rain-affected track while her coat still looks wintry.

"If it wasn't for spring aspirations you might say you'd wait for another day," Griffiths said.

While not yet convinced Ariaz will run out the 1600m of October's Thousand Guineas, Griffiths says the filly deserves a chance to prove him wrong.

"If you think that you're good enough you've got to run in this, then in a couple of weeks time and then aim for the Guineas Prelude and make a decision after that," Griffiths said.

"That's why there's the slight urgency to get the prep going and just see where she marks herself.

"If she can overcome a wide barrier and please us then she ticks box one and we're on our way heading down that optimistic path.

"If she doesn't then I've got plenty of time to change things up and have her ready for a 1200-metre race on Cox Plate weekend or during Cup week or even keep her for a week later at Sandown."

Ariaz showed her credentials when she ran down Motown Lil in a 1000m two-year-old fillies race at Sandown on debut before running second in a Group Three race over 1200m in Adelaide in April.