Stuart Clark, the Australia fast bowler, has welcomed the bold approach taken by Kevin Pietersen to next year’s Ashes series, but insists the new England captain’s confidence is misguided.

Pietersen declared England would beat Australia next summer if his side manage to replicate the form shown in defeating South Africa by six wickets in the fourth Test on Monday.

Clark commended Pietersen for delivering an aggressive statement of intent after only one Test in charge. “Kev is very good with that sort of stuff. He is a very forthright person, he has very strong opinions he believes in,” Clark said.

“It’s going to be a big series, it was a big series out here last time and it will be a huge series when we go there.

“That’s the rivalry that cricket needs to thrive in the longer version, not just Twenty20.

“Cricket needs that controversy and excitement between two countries.”

Australia defeated England 5-0 in the 2006/7 series, having recovered from their defeat in England in 2005 and Clark warned that his side are not prepared to lose the Ashes again.

“We haven’t lost many Test matches since 2005, so if form is anything to go by we’ve probably got them," he said.

“Kevin is good at making statements. He truly believes it. Good luck to him.

“If he’s thinking about cricket in one year, I would have thought he’d want to worry about what’s happening in the next few months.

“But he’s the new captain and full of bravado. If he loses a few Tests, we will see if he’s still saying something then.”