Stuart Clark's 5-55 on debut has helped restrict South Africa to only 205 and Australia lost the wicket of Justin Langer while easing to 63 -1 on an eventful opening day of the first Test at Newlands in Cape Town.
Langer (16) was adjudged lbw to Andre Nel, bowling around the wicket, in the 10th over, and Matthew Hayden (22no) and Ricky Ponting (20no) survived the remaining 13.1 overs until stumps.
Earlier, Clark became the 13th Australian to take five wickets in an innings in his first Test, and Michael Kasprowicz (2-44) and Brett Lee (3-37) took the other five wickets to sink the Proteas in just 63.5 overs.
Clark dismissed Graeme Smith (19), Jacques Kallis (6), Herschelle Gibbs (18) and Mark Boucher (16) in his second, third, sixth and 11th overs, while Kasprowicz removed AB de Villiers (8) and Jacques Rudolph (10) in his fifth and eighth overs.
Lee returned for his second spell to dispose of Ashwell Prince (17) and Andrew Hall (24) nearing tea and Clark dispensed with Nicky Boje (31) and Lee pinned Nel (18) lbw to end the innings.
South Africa slid to 124-7 off 43.3 overs before the last three wickets added 81 in 20.2 overs, including an aggressive last-wicket stand of 32 - the highest of the innings - in six overs between Nel and Makhaya Ntini.
Smith won the toss and chose to bat first despite admitting before the start of play that the pitch had 'a little dampness' in it, and Australian captain Ponting said it contained 'a bit of moisture', while adding he also would have batted first.
Having been presented with his baggy green cap by former Australian Test paceman Merv Hughes, now a national selector, Clark, 30, had the startling figures of 3-13 off six overs in South Africa's lunch score of 4-66 off 27 overs.
Kasprowicz gained the first breakthrough in only the 10th over by bowling de Villiers (8) with a perfect off-cutter.
Clark then angled his ninth ball across left-hander Smith and wicketkeeper Adam Gilchrist accepted the edge low to his left in the 18th over.
Next over, Kallis cut Clark straight to Hayden, the wider of two gullies, who accepted a comfortable catch.
Gibbs lost his off stump to a Clark leg-cutter in the second-last over before lunch, and, wicket to wicket, the Test debutant had taken 3-10 in four overs for figures of 3-13 off six overs at the break.
Kasprowicz struck again with the eighth ball after lunch when he induced an edge from left-hander Rudolph to first slip where Shane Warne spilled the catch but kicked the ball up from a prostrate position before it hit the ground and Gilchrist completed the catch.
Then, in the ninth over after lunch, Boucher edged a Clark leg-cutter and Gilchrist dived at full stretch to his right to take a brilliant low catch in his right glove, giving him the brilliant figures of 4-29 as South Africa slumped to 104-6.
Lee had Prince and Hall - both cutting off the back foot - caught by Hayden in the gully in the second and sixth overs of his second seven-over spell.
South Africa was 155-8 off 54 overs at tea, and Clark claimed his fifth victim in the fourth over after the break, nailing Boje lbw before Nel and Ntini each clouted a six - Nel off Clark, Ntini off Warne - during their lusty liaison.