Glenn Thornton has decided on a Moonee Valley start for Vibrant Rouge but the mare will only run on a suitable track.

Thornton decided the 1200m mares' race at Moonee Valley on Saturday was a more suitable option than the Golden Topaz over the same distance at Swan Hill on Friday.

Unbeaten three starts at Moonee Valley, Vibrant Rouge is at her best on good ground and expected track conditions played a role in the trainer's decision.

Vibrant Rouge is also unbeaten in three starts at Moonee Valley.

"If she runs it will be at Moonee Valley," Thornton said.

"It's still a dead five track at the Valley at the moment and it's a slow six at Swan Hill. I'm erring on the side of caution and I don't think she needs a five-hour trip to get to the races (at Swan Hill).

"They are both similar races and if anything the Moonee Valley race looks a bit more suitable."

The five-year-old finished fourth at her most recent start in the Group Three Proud Miss Stakes in Adelaide last month on a slow track.

Thornton said Vibrant Rouge gets through rain-affected going but did not excel in those conditions.

The Geelong trainer will keep monitoring the weather in the lead-up to Saturday.

"I'll be accepting to run at the Valley and if we're lucky enough to get reasonable weather, I'm sure she'll run a great race," he said.

Vibrant Rouge won a restricted fillies and mares race at Moonee Valley in 2012 and claimed back-to-back wins at the track over 1200m last preparation.