Kevin Pietersen is predicting an England success in next summer's Ashes series if his side can maintain their level.

Pietersen was so impressed with the England players during their six-wicket triumph over South Africa in the final match that he is already sounding bullish, 11 months before the opening Ashes Test in Cardiff on July 8 next year.

"If we play like we played this week, we will beat Australia, but it's going to take a lot to do it," claimed Pietersen, who only became captain last Monday following Michael Vaughan's tearful resignation speech a day before.

"This was a one-off, it was a very exciting stage, a starting stage and the most important thing will be to turn up to every single Test match like we've done this week.

"My main driving force for this team is to be, every single day, up for the challenge of improving, having no comfort zones and testing the guys out to perform every single day."

That type of bold prediction has a habit of backfiring, but Pietersen is happy to increase the expectations on himself as he completes his first week as captain and has admitted he is already thinking about the battle with Australia next summer.

Before then England tour India and West Indies this winter and have a home Test series against Sri Lanka, but it is the challenge of taking on the world's best side which is already taxing him.

"I've done a lot of thinking over the last few days," he admitted. "You do find yourself thinking about the game more, and scenarios.

"I've certainly done some thinking about Australia next year, a lot more than when I would have when I was a player because you want to get the structure right, so guys can play in certain positions, feel comfortable, know their role and deliver.

"It will be important over the next nine months to learn their roles and then deliver."

Pietersen has already revealed that strike bowler Steve Harmison is going to play a key role in that vision following his outstanding return to Test cricket at the Brit Oval this week, where he claimed four wickets on his comeback.

That included a half-hearted attempt to persuade Harmison to reverse his decision to retire from one-day international cricket which was predictably rejected by the Durham fast bowler.

"I asked over lunch yesterday," confirmed Pietersen. "He said he would see but the travel has always been the problem for Steve, being away from his family.

"I respect the man for the decisions he makes and it would be lovely to have him coming in first change with the white ball, but you don't always get what you want in life.

"We've seen this week how important he's going to be for us. He's a huge player. I'm going to be looking after Steve as much as I can but also making sure I get the best out of him and I think I know the sort of ways to do it."

South Africa captain Graeme Smith, whose side claimed their first Test series win on English soil since 1965, admitted the celebrations over their achievement at Edgbaston last week may have affected their performance in the final Test.

"Whatever I say, I don't want to take anything away from England's victory," said Smith. "I think they were motivated, but I think they came out and played the better cricket in the game.

"I think the emotion that we felt after winning at Edgbaston was always going to be difficult to re-invent and bring into this game and I think that showed in the way we performed.

"We would play well for an hour and a bit then we'd lose our way a bit and I think maybe that showed in terms of the series having been won, how much it meant to us at Edgbaston."