The team behind champion racehorse Winx is open to the mare going for a record fourth Cox Plate, but also concerned how racing overseas could affect her preparation.

Part-owner Peter Tighe says running in the Cox Plate in October depends on whether or not Winx races overseas at Royal Ascot in June - a decision which is yet to be made.

"It's all to do with the timing," Tighe told Sky Sports Radio on Tuesday.

"If we're going overseas and then coming back, and if it's all possible to play it out and do that without stretching her too thin."

Tighe said a decision to take the mare overseas or not was imminent, but that it was up to Winx's trainer Chris Waller to make a "good, well-timed, judged decision."

"It's a huge temptation to take the world on. We know she's good enough and she'd certainly be competitive wherever she goes but we're still keen to race in Australia," Tighe said.

The remarkable mare is in the spelling paddock, having won a record-equalling third Cox Plate last month and becoming the first horse in Australian racing history to amass more than $15 million prize money.