The Aussie star said that she and her English boyfriend, Kris Smith, will definitely be rival fans during series, which is now underway Down Under.
The star, interviewed in London by Shane Warne for the Aussie spin king's talk show, Warnie, said:
'It's a nightmare if you're Australian and you lose the Ashes and you get in a black cab in London because you cop it from the driver, big time.
'I can tell them I'm not bothered but they give it to you the whole journey.
'It's awful. We've got to win.'
She added: 'Of course Kris and I will be rivals.
'I want to sing him the victory song at the end of the series, not the other way around!'