Ricky Ponting's Australia are now just one defeat away from losing their world number one crown after South Africa crushed them by nine wickets in the second Test to register their first ever series victory Down Under.
Having taken an unassailable 2-0 lead in the series, South Africa will topple Australia from their top ranking if Graeme Smith's men can win the third and final Test in Sydney.
Resuming on 30 for no loss, South Africa needed 42 overs to score the remaining 153 runs for a memorable win and the moment came soon after lunch when Hashim Amla flicked Michael Clarke behind square leg for two runs.
In a match where Smith struck two fifties, JP Duminy scored his maiden hundred and Ponting scored 101 and 99, Dale Steyn was adjudged Man of the Match for his match haul of 10 for 154 besides the crucial 76 he scored in the first innings.
Graeme Smith was the lone South African wicket to fall in the second innings. The South African captain was trapped leg before by Nathan Hauritz after making a 94-ball 75 with 10 boundaries in it.
Fellow opener Neil McKenzie (59) and Amla (30) remained not out after guiding the team to a historic win.
Ponting, meanwhile, became the first Australian captain in 16 years to suffer a series defeat on home soil. Last time Australia lost a series at home was against the West Indies in 1992-93.
More than their bowling attack; Australia's slim chance of saving the match depended on rain.
Though there was slight drizzle in the morning, play started on schedule and South Africa could not be denied the win they thoroughly deserved.