Brett Lee ripped through fragile South African batting and Andrew Symonds and Mike Hussey piled on the runs to help Australia to an 80-run victory in a limited-overs one-day match on Friday.
Symonds (65) and Hussey (62) plundered 109 runs off 79 balls to help Australia reach a daunting total of 281 for seven, before Lee captured four wickets to restrict the Proteas to 201-9 at Melbourne's Docklands Stadium.
Lee trapped Proteas captain Graeme Smith lbw for a duck on the second ball of the South African innings then captured three more wickets in his eighth over to finish with 4-30.
"I thought it was an excellent all-round performance tonight," Australian captain Ricky Ponting said in a televised interview.
"We always try and time our run during these competitions and build our momentum and we're getting better each match."
Lee was called into the Australian team on the morning of the match when Glenn McGrath withdrew after learning his wife had been diagnosed with cancer for the third time.
McGrath released a statement saying he would not be available for selection with his wife about to undergo radiotherapy treatment but that he intended to resume playing for Australia.
Australia made a bright start, Adam Gilchrist (33) and Simon Katich (25) getting the innings off to a flyer, but suddenly looked to be struggling when they lost Damien Martyn (34), Ponting (53) and Michael Clarke (one) in quick succession to slump to 137-5 in the 37th over.
But Hussey and Symonds quickly turned the match around, posting individual fifties and sharing a century partnership that thrilled the crowd.
Hussey's 62 came off only 58 balls and featured nine boundaries, including six fours from seven balls off Johan van der Wath. Van der Wath gave up 82 runs for his two wickets, including Hussey in the last over of the match.
Symonds made 65 off 60 balls, including 19 runs off one over from Smith, before he was eventually run out on the last ball of the innings.
The Proteas made a terrible start when Smith departed in the first over and Boeta Dippenaar (nine) was dismissed in the seventh over.
Super-sub Johan Botha (46), Herschelle Gibbs (33) and Ashwell Prince (24) tried to resurrect the innings but Lee destroyed their hopes when he was reintroduced into the attack and promptly got rid of Justin Kemp (20), Mark Boucher (no score) and Botha in the same over.
"We're disappointed we lost but we're going to have to pick ourselves up again," Smith said.
Australia are already assured of a place in the best-of-three finals while South Africa need to win one of their remaining two matches to claim the other spot ahead of Sri Lanka.
They play Australia in Sydney on Sunday then Sri Lanka in Hobart on Tuesday.