Isotope will go into her first major test without a barrier trial but has had two solid track gallops in preparation for the race.

Unbeaten Isotope hasn't run since winning at the Sunshine Coast on April 25 which was her second win from as many starts.

Trainer Tony Gollan elected not to trial her in the lead-up to the Group Two Champagne Classic at Eagle Farm on Saturday.

Instead Isotope worked with a partner between races at Doomben last week and had a nice gallop on the A grass at Eagle Farm on Tuesday.

Isotope will step up to 1200m for the first time but Gollan is sure she will handle it and the 1400m of the Group One JJ Atkins in a fortnight.

She is second favourite for the JJ Atkins but is likely to regain top mantle if she races well on Saturday.

Gollan said Isotope was not one-dimensional and he was sure she didn't have to lead in her races.

“You can basically put her wherever you want her in her races. She has led and she has sat behind them and won both times,” Gollan said.

He said Isotope's breeding suggested she would have no trouble with the 1400m in the JJ Atkins.

The filly is by top young sire Deep Field out of the mare Great Dansaar who is a half-sister to Spring Champion Stakes winner Yankee Rose.

“On her pedigree it won't be a problem with her,” Gollan said.