Mitchell Starc claimed his 20th five-wicket haul as South Africa slumped from 203-1 to 329 all out on the first day of the crucial third and final Test against Australia at Newlands.
The Proteas were 192-1 at the drink in the second session after Australia had won the toss and elected to bowl, with Marques Ackerman 95 off 94 balls.
Aiden Markram scored 78 and David Bedingham scored 50 before the middle-order collapsed as Starc took 6-72 – his best figures against South Africa in Tests – to set up a turnaround.
Markram and Ackerman had put on 140 by lunch, with Australia looking clueless after making four changes to the side – including dropping opener Nic Maddinson and giving Veteran Steve Smith ruled out due to injury
Ackerman was stumped for 95 by Nathan Lyon after charging the off-spinner, having hit 12 fours and two sixes before failing in his bid for his maiden Test century.
Markram – dropped by Starc in the morning session – added 45 with Bedingham as South Africa moved to 203-1, then Starc took a stunning catch at square leg to remove Markram from Josh Hazlewood.
Lyon caught captain Temba Bavuma for a three-ball duck and left-arm spinner Cooper Connolly took his first Test wicket as he trapped Matthew Breetzke lbw for two.
Starc removed Bedingham after tea and had Wiaan Mulder caught two balls later for a duck, with South Africa losing five wickets for just 29 runs before Marco Jansen (52) and Ryan Rickelton stemmed the tide.
Jansen scored a second successive half-century and Rickelton scored 42 as the pair added 95 for the seventh wicket, only for Starc to strike again with the second new ball to rip the tail.
Marco Jansen, left, celebrates his fiftieth with teammate Ryan Rickelton on opening day
Starc had Rickelton lbw in the 81st over and two balls later bowled Jansen, then took four wickets in six balls when he bowled Gerald Coetzee for a golden duck and removed Kagiso Rabada for another nil.
South Africa slumped from 327-6 to 329 to hand the momentum to Australia, who won the first Test in Durban by 214 runs before being beaten in the second by an innings and 31 runs in Gqeberha.
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