South Africa held a 411-run lead over Pakistan at the close of the second day of the first Test at the Wanderers on Saturday with seven second innings wickets still in hand after dismissing the visitors for their lowest test score of 49.
Fast bowler Dale Steyn took six for eight, his best figures at home, as Pakistan were bowled out in 29.1 overs four runs short of their previous worst innings total.
Graeme Smith then decided he would not enforce the follow-on and at the close his side were 207 for three in their second innings.
Openers Smith and Alviro Peterson (27) raced to 82 before the latter skied an Umar Gul delivery and Mohammed Hafeez completed the catch.
SA: 253 and 207/3 (AB de Villiers 63*, H Amla 50*, G Smith 52) vs Pakistan 49 (D Steyn 6/8)