Nottinghamshire spinner Graeme Swann returned the third five-wicket haul of his Test career to restrict South Africa to 418 all out in their first innings.
Having resumed on 262-4, South Africa will be pleased with their first innings total but England bowler Graham Onions, who supported Swann with 3-86, said England are determined to remain on the front foot having reached 88-1 at close of play on day three.
"There's no reason why we can't press for a result and hopefully get a win if we bat well,” said Onions.
“We've got a great opportunity to bat all day and build a healthy total."
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