Graeme Smith reckons South Africa's first Test series win in England for 43 years was even more impressive given their lack of firepower with the ball.

The Proteas headed into the four-match npower campaign with a much-heralded attack but of their bowling unit, only Jacques Kallis averaged under 30 while it was not until the final Test that Makhaya Ntini bagged the only five-wicket haul.

Spinner Paul Harris played no more than a holding role while Andre Nel's four wickets came at over 50 apiece and Smith said: "We didn't bowl nearly as well as we had expected on this tour."

He added: "Not having reached anywhere near our potential was disappointing.

"But the fact that we won the series and were 2-0 up after Edgbaston, is heartening for us because we know we have this huge ability to improve and yet we are still winning."