England continued to press home their advantage as they moved 303 runs ahead of South Africa at tea on day three of the fourth Test, reaching 2-86 in their second innings at The Wanderers on Sunday.
After dismissing South Africa for 183 at lunch, leaving their hosts 217 runs adrift, England did not enforce the follow on.
Instead openers Zak Crawley and Dom Sibley put on a 56-run opening-wicket partnership as they sought to put the game - and the four-Test series - further beyond South Africa's reach.
Crawley, who top scored for England in the first innings with 66, made 24 before he edged Dwaine Pretorius behind to wicketkeeper Quinton de Kock.
Joe Denly, who had not fielded at the start of play because of a migraine, made eight runs before being bowled by Dane Paterson but Sibley and captain Joe Root saw England through the rest of the afternoon session.
Sibley is now top scorer in the series and at tea was 39 not out with Root on 10.
South Africa's lead bowler Vernon Philander pulled up with a hamstring injury after nine balls, further weakening a home attack already sorely missing the suspended Kagiso Rabada.
Philander was sent to hospital for a scan, said Cricket South Africa, threatening an inglorious end to his test career as he is retiring from the international arena.
Mark Wood completed a five-wicket haul earlier as South Africa were dismissed in the morning session, adding 95 runs to their overnight score.
They were teetering at 6-88 overnight in response to England's commanding first-innings score of 400, and saw Philander dismissed with the fifth ball of the morning, but then offered a short spell of resistance as De Kock and Pretorius put on 79 runs for the eighth wicket.
But after Pretorius was expertly caught by Crawley in the gully off Ben Stokes, South Africa's last wickets fell quickly.
De Kock was bowled by Wood for 76 and the England paceman finished with 5-46 when he also dismissed Paterson.
England, leading 2-1, will be looking to set South Africa a target well over 400 runs and then try to bowl them out to complete a dominant series success.
Australian Associated Press
