Owais Shah has been backed to make the number three spot his own in England's one-day side after making his first major contribution in the new role to help secure another emphatic triumph over South Africa.

England's successive victories at Headingley, Trent Bridge and The Oval to secure the NatWest Series with two matches to play had all been achieved without the 29-year-old Middlesex batsman playing a major innings.

Since being moved to number three in the one-day side at the instigation of new captain Pietersen from his usual spot in the middle order, Shah had contributed only 35 runs in his two previous innings in the five-match series.

But all that changed at Lord's when Shah hammered an unbeaten 44 off only 40 balls to help England chase down a rain-adjusted victory target of 137 in 20 overs with 14 balls remaining to complete a seven-wicket victory.

"You give a guy confidence, and he knows he can come in and play his way and he's going to be backed," said Pietersen, who shared a 74-run stand off only 58 balls with Shah.

"I knew he was going to come good. He knew I had the confidence in him, and so did the players, and his county stats prove in first-class cricket he's a great player.

"He deserved a go at three. He's played some fantastic shots, and the way he was talking when I was batting with him was a really good sign of things to come."

Shah's performance, which included a six and four fours, was eventually overshadowed by man-of-the-match Andrew Flintoff, who hammered an unbeaten 31 off 12 balls to follow his impressive bowling of three for 21 from his seven overs.

Although Flintoff picked up the magnum of champagne, the Lancashire all-rounder insisted the credit should have gone to the previous partnership - and Shah's performance in particular.

"I came in and did what I did and probably took the glory - but the work had been done beforehand," said Flintoff.

"The partnership Kevin had with Owais allowed me to come in and play a few shots, because there are still four lads behind me who can do the same job.

"I've played a lot of cricket with Owais since he was about 14, and he's always been a special player - I think there's a hell of a lot more to come from him."

Sunday's convincing triumph gives England an impressive 4-0 lead as they prepare for the final match of the series in Cardiff on Wednesday when victory would secure their first NatWest Series whitewash and elevate them to second in the world one-day rankings - their highest rating since the rankings began.

"On Wednesday, we're going to deliver again," added Pietersen. "We're going to try our hardest to win 5-0 because there will be no greater satisfaction than to finish at 10.30pm and know we're second in the world."

Dejected South Africa captain Jacques Kallis, who is leading the side in the absence of the injured Graeme Smith, has called on his team to end the tour on a high and avoid the humiliation of a 5-0 series hammering.

"We pride ourselves on our results and even though there were positive signs at Lord's, we don't accept losses very well," said Kallis

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