At stumps, the Proteas were 145 for three in their second innings — a lead of 139 — with Amla 57 not out and nightwatchman Dale Steyn nought not out. South Africa, 1-0 up in the three-match series, only have to avoid defeat to replace England as the world's top-ranked Test side.
Amla, dropped on two, and Jacques Kallis (31) shared a third-wicket partnership of 81.
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