England encouragingly lost just one wicket in reply to South Africa's 418, after spending the majority of a second successive day toiling in the scorching Centurion sun.
The tourists got rid of overnight pair Jacques Kallis and JP Duminy for 26 runs between them early on the second morning of the four-Test series, yet were still in the field almost four hours later.
In 23 overs of batting, they then reached 88 for one - a promising response for a team whose mental state might easily have been frazzled by more than five sessions of full exposure to extreme heat at altitude.
It seemed Kallis (120) and Duminy (56) held the key to whether England would suffer a chastening experience for the second successive day.
Neither of the batsmen could add significantly to their existing contributions. But, despite a five-wicket haul for Graeme Swann, it was not until well into the evening session that England at last got their chance to bat - after Mark Boucher and the determination of the tail had prolonged their labours.
When England did finally begin their first innings, Makhaya Ntini would have marked his 100th Test appearance with the scalp of Alastair Cook for a first-ball duck had AB de Villiers not surprisingly dropped a head-high chance at third slip.
Debutant Friedel de Wet started his Test career with a horrific no-ball way down the leg side but quickly got over his nerves to gain revenge for consecutive Cook boundaries with a delivery which did enough from an awkward length to take the outside edge for a caught behind.
Andrew Strauss (44no) was joined by Jonathan Trott for the latter's first Test innings in his native country.
The Warwickshire batsman survived an unsuccessful lbw review from the bowling of slow left-armer Paul Harris, on 12. But England's second-wicket pair were otherwise in control in an unbroken stand of 63.
Duminy had earlier passed his half-century in a fifth-wicket partnership of 124 - the left-hander cover-driving James Anderson for his sixth four to add to one six from 120 balls.
A surface of occasional uneven bounce appeared to flatten out on the second afternoon, and the worry for England was that South Africa might be getting the best of batting conditions before wear and tear take their toll tomorrow.
Kallis' wicket came from a perfectly-pitched Anderson delivery, drawing South Africa's cornerstone into a forward push on off-stump and taking the edge when it bounced and held its line - for Paul Collingwood's third slip catch of the innings.
Even with Kallis' five-hour stay over, South Africa ploughed on and could be increasingly happy with their work - having been put in yesterday on a pitch dappled with green.
Duminy went in the hour before lunch to an action replay of Ashwell Prince's dismissal yesterday, Collingwood again the catcher at slip as Swann struck in his first over for the second day running.
Boucher had a slice of luck on 25 when Graham Onions failed to hold an awkward catch on the long-leg boundary from a mis-hook at a Stuart Broad bouncer.
The wicketkeeper had a second close call four runs later, edging a sweep down onto his boot off Swann for what would have been an all-time England record-breaking fifth catch of the innings for Collingwood at slip - had third-umpire replays not suggested the ball hit the ground before looping up.
Morne Morkel took a nasty blow on the side of the helmet, before wafting a catch behind to Matt Prior off Onions (three for 86).
But Boucher found a new ally in Harris to further frustrate and tire England until, one short of his 50, he got a thick inside edge to short-leg as Swann got one to bite from outside off-stump.
Still England could not finish off their hosts, though, Harris and De Wet in absolutely no hurry as they achieved another chunk of nuisance value.
Collingwood had a half-chance to pull off that fifth catch but put down a sharp one, diving to his left when Harris edged a cut at Swann on 24.
But a combination of first Onions and then Swann finally closed the home innings, England belatedly on the right end of a review ruling when Aleem Dar's lbw verdict against De Wet was upheld.