Smith became the first player since India's Vinod Kambli in 1992-93 - against England and then Zimbabwe - to score double tons in successive Test matches.

The 22-year-old had amassed 277 - his country's highest individual score - in the drawn first Test at Edgbaston.

And Smith reached the 200 mark again as he and centurion Gary Kirsten showed England no mercy in taking the Proteas towards a massive total.

Smith on-drove Anthony McGrath for three to attain his double century - off 287 balls with 27 fours.

Smith had already moved past 500 runs in the series in just three innings when he reached 138 but he showed no signs of flagging as Michael Vaughan's side toiled in vain.

If he continues this run of form then the highest run aggregate for a Test series will also be coming under threat - 974 by Sir Donald Bradman in the 1930 meetings with England.

Kirsten was content to play the supporting role but his contribution was also crucial in ensuring that England were offered no chink of light.

His 17th Test hundred - and fourth against England - was reached with his 14th four and spanned 229 deliveries.

England looked totally demoralised and the only chance offered was by Kirsten who was dropped by Mark Butcher on 54 at second slip after he edged an Andrew Flintoff delivery.

South Africa had resumed on 151 for one when play finally got under way 75 minutes late at noon after morning drizzle.

It was twenty past five before England made their first breakthrough of the day when Kirsten, on 108, chopped a delivery from Anthony McGrath onto his stumps. His partnership with Smith was altogether worth 247 in 70 overs.

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