Perth trainer Simon Miller believes an outside barrier will be a major plus as he chases his first Queensland Group One win with Platinum Rocker in the Tatt's Tiara on Saturday.

Platinum Rocker will jump from barrier 15 in a field reduced to 16 by the early scratching of Victorian filly Griante.

"I have been saying all along I want a sticky barrier for her," Miller said.

"I have been keeping blinkers up my sleeve for her and I will put them back on this Saturday.

"She will need to find a length against this field, which I think is pretty handy."

Platinum Rocker wore blinkers earlier in her career but Miller took them off after they began to make her race too keenly.

"I was worried if she drew an inside alley in the Tiara she might get cluttered up and over-race. This way she will be out and away from other horses in the first run to the corner as she looks for a position," Miller said.

Platinum Rocker has had three Brisbane starts this winter for placings in the Silk Stocking and Glenlogan Park Stakes before an unlucky fifth in the Group Two Dane Ripper Stakes at Eagle Farm two weeks ago.

Under the weight-for-age scale of the Tiara (1400m), the mare meets most of her Dane Ripper rivals on better weight terms.

"I am not sure she was suited under the quality scales where there are penalties and allowances," Miller said.

"She was getting big weights and I don't know if she is a weight carrier."

Platinum Rocker is lightly raced for a six-year-old with eight wins from 16 starts.

Her only other attempt at Group One level was in last year's Railway Stakes when she ran a close second to top West Australian galloper Luckygray.

Miller has been one of Perth's most successful trainers in recent years with a host of feature race winners but he admits he has a special spot for Platinum Rocker.

"I would love her to win a Group One race. She is so honest she deserves it," he said.

Meanwhile, trainer Ciaron Maher has confirmed a slight hoof problem is behind the decision not to accept with smart filly Srikandi in the Tatt's Tiara.

"She has done a very good job this winter and we don't want to push her," Maher said.