Only England's third such victory margin put them 2-0 up in the NatWest Series and, to make matters worse for the tourists, captain Graeme Smith is an injury doubt for Friday's third match of five.

Stuart Broad claimed a maiden five-wicket haul in one-day internationals to set up the rout, and Pietersen admitted: "It was spectacular. In the four or five years I have played one-day internationals we have not hammered a team as convincingly as that before. There's an energy and a buzz about us."

That has proved quite a contrast to the mood earlier this month when the South Africans sealed the Test series and Michael Vaughan and Paul Collingwood relinquished their captaincy positions.

"The way the guys have turned themselves around has been remarkable," added Pietersen.

"Really exceptional. But I think I am in a fortunate position to have four bowlers bowling at 90 miles per hour - and I am sure if previous captains had them firing on all cylinders at the start of their campaign, or whenever it was, I am sure they would have been alright."

Broad's spell of 10-3-23-5 from the pavilion end left the South African innings in tatters at 53 for seven.

"It is great being a part of this bowling unit," said Broad after being named man of the match.

"You have got the knowledge and experience of Fred (Andrew Flintoff) and Harmy (Steve Harmison) who are always passing it on, and it's thoroughly enjoyable.

"The wicket had some bounce in it from a good length, it didn't have demons in it, but the nicks went for us and we took our catches."