South Africa (0) 15
Tries: Jacobs 2 Con: Montgomery Pen: James
Australia (10) 27
Tries: Robinson, Tuqiri, Mortlock Cons: Giteau 3 Pens: Giteau 2
Lote Tuqiri's try put Australia in command
South Africa slipped to their third successive Tri-Nations defeat as Australia won on Springboks soil for the first time since 2000 in Durban.
The visitors enjoyed a 10-0 half-time lead via an early Matt Giteau penalty and Benn Robinson's close-range try.
A Butch James penalty finally put South Africa on the scoreboard.
But a Giteau penalty and Lote Tuqiri's try on the hour made it 20-3 before Adrian Jacobs scored two tries either side of Stirling Mortlock's clincher.
It was only Australia's second victory in 16 Tests in South Africa since the Springboks were readmitted to international rugby in 1992.
The teams face each other again in Johannesburg next week, with the hosts now out of the Tri-Nations reckoning after a fourth defeat in five matches.
But regardless of the result at Ellis Park, the Wallabies' victory in Durban ensures they will face a winner-takes-all title decider against New Zealand in Brisbane on 13 September.
That represents excellent progress under new coach Robbie Deans, but his Springboks counterpart Peter de Villiers is now under increasing pressure after another lacklustre display at the ABSA Stadium.
The hosts again struggled at the breakdown, as they had in their 19-0 defeat by the All Blacks a week ago.
Giteau punished some Boks foul play with a penalty in the ninth minute before Robinson scored the opening try just before the half-hour, the video referee adjudging the prop had grounded the ball despite Jean de Villiers' tackle.
Giteau's conversion made it 10-0 at the interval, James landing the hosts' first points on the resumption - and their first in 125 minutes of Test rugby - before giving way to Francois Steyn at fly-half after 55 minutes.
By then Giteau had landed another penalty and Jacobs was forced to scramble back desperately to deny Tuqiri.
But the powerful wing collected his 30th Test try - drawing level with Joe Roff and Tim Horan at third on the Wallabies all-time list - when he stepped out of a Fourie du Preez tackle and scrambled over.
Giteau's conversion saw the Boks staring at a 17-point deficit going into the final quarter.
Jacobs gave them hope with a smartly-taken score minutes later, Percy Montgomery - on as a replacement - adding the extras.
But Mortlock swiftly ended any thoughts of a late comeback when he cut inside and bludgeoned his way through some flimsy tackling for a decisive try converted by Giteau.
Jacobs grabbed a second from Montgomery's deft inside pass, but the Springboks were booed off after another dispiriting defeat.
South Africa: Conrad Jantjes; JP Pietersen, Adrian Jacobs, Jean de Villiers, Jongi Nokwe; Butch James, Fourie du Preez; Tendai Mtawarira, Bismarck du Plessis, CJ van der Linde, Andries Bekker, Victor Matfield (capt), Schalk Burger, Juan Smith, Pierre Spies.
Replacements: Adriaan Strauss, Brian Mujati, Joe van Niekerk, Luke Watson, Ricky Januarie, Francois Steyn, Percy Montgomery.
Australia: Drew Mitchell, Peter Hynes, Stirling Mortlock (capt), Berrick Barnes, Lote Tuqiri, Matt Giteau, Sam Cordingley; Benn Robinson, Stephen Moore, Matt Dunning, James Horwill, Dan Vickerman, Rocky Elsom, George Smith, Wycliff Palu.
Replacements: Tatafu Polota-Nau, Al Baxter, Hugh McMeniman, Phil Waugh, Brett Sheehan, Timana Tahu, Ryan Cross.