The Myer Classic distance is the only query trainer Robert Smerdon has with Politeness ahead of her spring grand final.

Smerdon has targeted Politeness at Saturday's 1600m feature for fillies and mares at Flemington.

Winner of the Group Three PJ Bell Stakes (1200m) for fillies in the autumn, Politeness will be making her Group One debut in the Myer.

"She's still on trial at the mile but we've always thought she would run it," Smerdon said.

"She's drawn a slightly awkward gate in barrier 10 for a get-back horse, but we've just got to deal with that."

Smerdon believes the key to the chances of Politeness will be a genuine tempo in the big field.

"If there is good speed on and she gets cover she will relax and then she gets her chance," he said.

Politeness was fifth in the Group Two Tristarc Stakes (1400m) at Caulfield last start behind the Gai Waterhouse-trained Sweet Idea who added another stakes race win to her resume.

Sweet Idea is second favourite for the Myer at $5.50 behind Australasian Oaks winner May's Dream ($4.80) who came from back in the field to finish fourth in the Tristarc.

A multiple Group One placegetter, Sweet Idea will be having her first test at 1600m but Waterhouse, who also has Group One winner Diamond Drille in the race, believes Sweet Idea will have no problems with the distance.

"I can't see why she can't win again," Waterhouse said.

"She's a class mare and this is the right race for her."

Third favourite Catkins, a close runner-up to her former stablemate Red Tracer a year ago, is the third pick at $7.50.