England´s nemesis Hashim Amla overcame a battered thumb and a lively wicket to post 50 not out and guide South Africa to 121 for four at lunch on day four of the final Test on Monday.
The Proteas led by 254 runs on a rapidly deteriorating wicket with Amla and Temba Bavuma (nine not out) seeking to set England a record-breaking target if they are to win the series 3-0.
The touring side bowled well in the morning session, with James Anderson grabbing two early wickets and Ben Stokes another.
They have yet to dismiss Amla, though, as he showed great patience and steel while in obvious discomfort after being wrapped on the glove by Stokes on day three.
He took his series runs tally to 424 at an average of 70.66 and remains the key in the Proteas posting a fourth-innings target they will feel is beyond England.
Anderson had earlier taken his number of Test wickets to 433, one short of Indian great Kapil Dev in sixth place on the all-time list.
He first induced a rash drive from opener Stephen Cook (25) that provided a catch for wicketkeeper Jonny Bairstow and two balls later grabbed the big scalp of home captain AB de Villiers, lbw for a duck.
It would have been a satisfying moment for Anderson after De Villiers had suggested before the game that England´s bowlers had lost pace, with many suggesting he was alluding specifically to Anderson.
It was also the third duck in a row for De Villiers, comfortably his worst run of form in test cricket since he made his debut in 2004.South Africa still have first-innings centurion Quinton de Kock to bat before England are in to the tail, but chasing anything over 300 on a wicket with variable bounce and movement will be extremely difficult.
It would also be a record, the previous highest chase in test matches on this ground was 251 by England in 2000, though the pitch was only used for two days in that match after rain spoiled the test and the teams decided to forfeit an innings each to force a result.
