Root claimed Check-best figures of 4-31 and was ably assisted by Stuart Broad and Mark Wooden as South Africa ended the fourth day nonetheless 188 runs adrift.
England want 4 extra wickets to win their 500th abroad Check and take a 2-1 lead within the four-match collection, whereas the beleaguered dwelling group might want to bat out your entire day, a job that appears close to inconceivable given they’ve run out of recognised batsmen.
Vernon Philander (13) and Keshav Maharaj (5) resume on Monday.
England began the day with fast success and saved up the stranglehold regardless of a prolonged delay for rain, emphasising the dominance they’ve loved since day one.
South Africa had been in serious trouble after they resumed on 208/6 of their first innings, nonetheless 291 behind England’s mammoth 499 for 9 declared.
Any hopes of a defiant stand crumbled instantly as England, impressed by Broad, took 4 wickets for the addition of 1 run to finish the innings contained in the opening half hour.
South Africa had been made to follow-on and had been 15-Zero when the rain got here however as soon as the skies cleared, Wooden rapidly eliminated opener Dean Elgar (15) and the struggling Zubayr Hamza for 2.
Root got here on for an extended spell throughout which he trapped Pieter Malan lbw for 12 and Rassie van der Dussen, who survived a number of scares, for 10, with Ollie Pope at quick leg taking an excellent one-handed catch.
The competition was successfully over when Quinton de Kock went cheaply, misjudging his stroke and being acrobatically caught by Wooden as Root snagged his third wicket, adopted by the all-important scalp of under-pressure skipper Faf du Plessis, who edged one onto his pad and into Pope’s secure fingers for 36.
Root, a part-time off-spinner spinner, had not taken greater than two wickets in a Check innings however the way in which he ran by the highest order ought to result in vital South African soul-searching.
The hosts received the primary Check in Pretoria by 107 runs however had been outplayed by England within the second in Cape City.
The final Check begins in Johannesburg on Friday.