Co-owner Phil Sly has got out of his sick bed to make the trip to Flemington where Politeness has landed her first Group One win in the Myer Classic.

Battling an aggressive form of cancer, Sly checked himself out of hospital three weeks ago to be trackside for the mare's victory in a Group Three race at Caulfield.

And his trip to Flemington for the opening day of the Melbourne Cup carnival on Saturday almost didn't happen.

"They've taken a few layers of bark off me and they've got me on a new drug which isn't doing the right thing by me," Sly said.

Ridden by Dwayne Dunn, Politeness ($19) scored a three-quarter length victory from Fenway ($26) with Azkadellia ($11) a short neck away third.

Dunn replaced regular rider Mark Zahra aboard Politeness after Zahra was suspended for 22 meetings.

With the pattern of racing giving advantage to horses close to the rail, both trainer and jockey felt the best way to ride the mare was to go back from her middle draw and try for luck.

However Sly said to take the mare to outside, her normal racing style.

"This mare has come into her own now and she's won a Group One now."

The win for Politeness has secured her value as a broodmare after Sly and renowned Japanese breeder Katsumi Yoshida had considered sending the mare to Japan earlier in the season.

Sly said Politeness would now stay in training and be set for an autumn Sydney campaign.

Smerdon said he felt for Zahra who had won on Politeness at both her starts this campaign.

"It's been a harsh penalty," Smerdon said.