Prominent owner-breeder Peter Gleeson is hopeful his star filly Very Pretty will be fit to tackle the Victoria Oaks in October after her shock scratching from the Vicbred Super Series.

The multiple Group 1 winner was ruled out of the VSS three-year-old fillies' heats earlier today.

"She was behaving like she was tying up, (co-trainer) Clayton (Tonkin) had the vet to her, they've pulled some blood and decided she's got a low-level virus if you like," Gleeson said.

"Hopefully she will get over it fairly quickly and that's all we know at the moment."

The daughter of American Ideal has won nine of 10 career runs, including a last-start demolition job of her rivals in a scintillating 1.50.4 at Melton on August 17.

Very Pretty was set to start as a red-hot favourite in tomorrow night's fourth heat for three-year-old fillies at Kilmore, but her scratching leaves the race and series wide open.

The top six place-getters in each of the four heats progress to semi-finals on September 7, with qualifiers then moving through to the Group 1 final on September 14.

The Victoria Oaks remains a major target for Very Pretty, with heats for that feature scheduled for October 5.