Shane Warne
Shane Warne believe Australia will regain the Ashes if Kevin Pietersen is ruled out for England. [Reuters]

Shane Warne believes that if Kevin Pietersen is ruled out of the Ashes series due to injury then Australia will be able to defeat England and regain the famous little urn.

Pietersen missed the test series with New Zealand and was not named in the 15-man squad for the ICC Champions Trophy as he is still recovering from a serious injury lay-off and has only just returned to batting in the nets.

The destructive England batsman played a major part in England winning the Ashes in 2005, 2009 and 2011 and there have been question marks over how the side will cope without him.

Despite the comfortable victory over New Zealand, Pietersen would be a major loss and Warne believes his absence would give Australia the perfect chance to win an Ashes series in England for the first time since 2001.

"If Kevin Pietersen's not available for the Ashes I think Australia will win," Warne told Sky Sports."I think he's that big a player for the England team.

"Everyone feeds off him. He's such a destructive player, he can come out and get some low scores, but he's such a destructive player.

"If Kevin Pietersen plays then I still think Australia can come out and surprise England but I think if he's unavailable for the Ashes, which we don't want, we want him to be playing, everybody does as a cricket lover.

"But I think if Kevin Pietersen's not playing for England then Australia will win."

England are the favourites to retain the Ashes but Warne warns that even if Pietersen if fully fit, the Australians could cause an upset.

"England are definitely favourites," added Warne. "They've been playing some excellent cricket, and they're well led by Alastair Cook.

"But I really believe Australia have a squad, if they pick the right players and they perform then, I think the people who are out there writing them off could really be surprised."