England need six wickets on the final day to complete victory in the first Test against South Africa in Durban.
Steven Finn (3-27) reduced the hosts to 136-4 at stumps on Day Four after England had set them 416 – the second highest chase ever – to win.
Earlier, Jonny Bairstow hit 79 – his best Test score for three years – and Joe Root scored 73 as England reached 326 in their second innings.
England are heavy favourites to earn victory, but key batsman AB de Villiers remains unbeaten on 37. He was reprieved six overs before the close when Bairstow missed a tough chance to stump him off the bowling of Moeen Ali.
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