New captain Pietersen predicted that England would beat Australia next year if they reproduced the form which saw them defeat South Africa at The Oval in August. Warne, though, believes they must first get the ball rolling by winning in India and the Caribbean this winter.
"It was exciting for England, I suppose, to win a Test match against South Africa," he said. "It's encouraging, but I wouldn't get my hopes up too high.
"If England can win their next Test series, and then the next one, I'm sure they will give Australia a real shake and it will be a hell of a contest.
"But if they keep losing, then I think Australia will thrash them. Wipe the floor with them."
Warne also believes England need former captain Vaughan back in their team. "To me he's still the best No3 England have got," he said.