England managed to get 10 South African wickets on a rain-curtailed day on Sunday to move to the brink of a dominant victory in the third test and an unbeatable series lead.
The tourists crashed through the South African batting lineup twice on the fourth day in Port Elizabeth, first taking four wickets in less than five overs at the very start to bowl the home team out for 209 in its first innings.
Then, England captain Joe Root led with four wickets with his part-time offspin as South Africa slumped again to 102-6 at stumps in its second innings.
Root’s young England team, half of which is under 25, was on the way to a landmark win. England is expected to see out victory on the final day on Monday and take a 2-1 series lead with one test to play.
The South Africans were still 188 runs from England's first-innings score of 499-9 declared and faced a psychologically scarring defeat ahead of that series finale in Johannesburg.
England's fast bowlers ripped through South Africa first. Stuart Broad took three of the four wickets in that devastating early England spell, when South Africa nose-dived from 208-6 to 209 all out in its first innings.
That gave England a 290-run first-innings lead and Root made South Africa follow on.
Broad took his three wickets in 16 balls. Sam Curran had the other one, and three of the four were convincingly bowled as South African stumps flew in all directions.
Broad bowled Vernon Philander (27) in the first over of the day with a ball that smashed into Philander's off and middle stumps.
Curran did the same to Quinton de Kock, who was 63 not out overnight but had his middle stump uprooted in the second over of the day. Neither of the two batsmen added a run to their overnight scores.
Broad bowled tailender Keshav Maharaj for a duck in the next over. Again, the ball clattered into Maharaj's stumps — this time off a bottom edge — and England was utterly rampant under cloudy skies.
Broad had this third wicket in three overs when Kagiso Rabada hit a simple catch to Mark Wood to be last man out and England finished the job in the first 28 balls of the day for a resounding statement.
South Africa had shown a hint of resistance on the third day through de Kock and Philander's half-century partnership. That was ruthlessly swept aside the following morning.
Broad finished with 3-31 after England's blitz. Spinner Dom Bess took 5-51 and England didn't even need him to finish off South Africa's first innings.
The rain then did what no South African could and held up England for more than three hours.
The tourists picked up where they left off in the afternoon when quick bowler Wood ruined opener Dean Elgar's stumps to start the second-innings onslaught.
South Africa was 44-3 at tea and in danger of losing by an innings with a day left.
South Africa captain Faf du Plessis fought for his team's life with his 36 but it was only a brief fight. He was out to opposite number Root to a bat-pad catch that he strangely reviewed, and South Africa appeared all but done with just the bowlers left to try and save the test with the bat.
