Australia were splintered for 47 after South Africa had been routed for a comparatively bountiful 96 on the second afternoon of the first Test at Newlands, an afternoon that stretched the bounds of comprehension. The visitors' total was their lowest since 1902.
They batted a second time with a handsome lead of 188 after a staggering spell from Shane Watson and a merely excellent one from Ryan Harris appeared to have placed the match in their keeping. But they were 13 for three by tea and lost a frantic 6-8 on the resumption.
Vernon Philander and Morne Morkel were the chief executioners for South Africa, bowling magnificently in helpful conditions, but it must be said they had plenty of help from the batsmen.
At 21 for 9 Australia were still five short of the lowest innings' total in Test history, but Peter Siddle and Nathan Lyon put their batting counterparts to shame with a last-wicket stand of 26. Their determination contrasted with the unbridled panic of others on a pitch that, while difficult, was never so poor as to be threatening the slimmest total in Tests.
Morkel had Phillip Hughes and Michael Hussey edging off consecutive balls, on either side of the tea break, into the slips cordon. Philander swung and seamed the ball to continue the most striking of debuts, but was helped by a handful of ordinary shots from Australia's batsmen.
The worst of these was played by the wicketkeeper Brad Haddin, an ugly smear at a ball nowhere near the line or length to attack, and the rest either edged deliveries that seamed away or simply missed others that fizzed unerringly towards the stumps.
Not until Siddle and Lyon was there any semblance of calm shown by the visiting batsmen. Australia appeared to be unsettled significantly by the back stiffness that forced Shaun Marsh out of No. 3 in the order. He eventually shuffled to the middle at eight down, in obvious pain, and was lbw second ball.
Such a scenario seemed a world away when Watson and Harris were tearing through South Africa in the hour after lunch. Aided by a seaming pitch and alert use of the DRS, Watson and Harris orchestrated a tumble of wickets that at the time felt definitive. The hosts surrendered 9 wickets for 47 runs, momentarily looking as though they might fall short of the follow-on mark when 83 for 9.
The cascade of wickets added further lustre to a monumental 151 by Australia's captain Michael Clarke, who had shepherded the tail on the second morning to reach an ultimately handsome total of 284 from the overnight tally of 214 for 8.
Watson then transformed what had previously been a sedate start to South Africa's innings, in the first over after lunch. His second ball struck Hashim Amla in front, and the batsman was given out on referral to the third umpire. Jacques Kallis miscalculated a pull shot off the sixth ball, which lobbed into the slips off bat and body. As with Amla, he was given out on referral.
A handful of overs later Watson did in Graeme Smith, knocking a seaming delivery back onto his stumps, and next ball Ashwell Prince was palpably lbw to a full delivery that swung back in.
AB de Villiers fell next, bat and pad wedged closely together but adjacent and lbw to Harris on referral, and Watson had a fifth wicket inside four overs when Boucher was pinned lbw on the back foot - his referral would be unsuccessful.
Vernon Philander edged to third slip, Morne Morkel was run out by Peter Siddle's direct hit while taking a haywire single, and after the briefest of nuisance stands, Imran Tahir was bowled by a Harris ball that seamed away to complete an innings that rendered most observers speechless.
In the morning session there had been little indication of the tumult to follow.
Resuming at 214 for 8 in front of a sparse crowd, Clarke and Siddle showed the intent to score, but might both have been out inside half an hour. Philander's first ball of the day flew off the edge of Clarke's bat through second slip, but Graeme Smith hadn't posted one. Siddle had only five when Steyn found his edge towards backward point, where Imran Tahir allowed the chance to slip completely through his fingers as he tumbled forward.
The batsmen made South Africa curse these early misses, playing with level eyes, plenty of enterprise and some luck to add 59 in all, the second highest partnership of the innings. Clarke went on to turn his century into a truly momentous score, responsible for comfortably more than half of his side's total.
Eventually Siddle miscued Morkel to cover, and the last man Lyon hung around while Clarke fired off two more boundaries to pass 150. Clarke lost his leg stump when trying to swing Morkel for another, but he walked off knowing he had given his men a chance.
Marsh could not take the field, his place taken by the 12th man Trent Copeland, whose demotion from the XI meant Johnson shared the new ball with Harris. There was little early movement, the sun arriving to coincide with the start of South Africa's innings, and after two expensive overs Johnson was withdrawn without delivering a ball to Smith.
First-change Peter Siddle extracted the first significant seam movement of the innings, while Harris worked into a typically exacting spell. Moving the ball a little both ways, he made Rudolph use his bat, and eventually the batsman played around one that straightened the merest fraction to pluck out off stump.
Amla and Smith made it through to lunch, but obliteration waited on the other side of the interval - for both sides.