England cricketer Jonny Bairstow fell five runs short of a maiden test century before South Africa safely negotiated the start of their second innings, reaching 145 for 3 at stumps on day three of the third and final test against England at Lord's.
Hashim Amla was 57 not out with night watchman Dale Steyn on zero as the Proteas took a lead of 139 runs, with six sessions remaining in the match and series.
England were earlier bowled out for 315 in reply to South Africa's first innings 309.
Fast bowlers Morne Morkel and Dale Steyn did most of the damage for the tourists picking up four wickets each.
England must win the match to square the series and prevent South Africa leapfrogging them at the top of the world rankings.