Australia wing Digby Ioane scored a superb mid-second half try to set up a 25-19 triumph over Argentina on Saturday in a penalty-saturated final match of the Rugby Championship season.
A Wallabies team severely depleted by injuries were clinging to a three-point lead at a packed 40 000-seat Estadio Gigante de Arroyito in Rosario when awarded a scrum in Los Pumas territory 15 minutes from time.
The ball came back swiftly to flyhalf Kurtley Beale and Ioane drifted in from the left wing to take a pass, cut clean through the Argentine defence and dot down under the crossbar.
Makeshift fullback Mike Harris converted to give Australia a 22-12 lead that he increased eight minutes later with a penalty which lifted his personal contribution to 20 points.
Argentina set up a tense finish after Australian replacement scrumhalf Brett Sheehan was sin binned with another substitute, wing Juan Imhoff, claiming a pushover try that outside centre Marcelo Bosch converted.
Beale missed a late penalty, offering Argentina a chance to snatch victory by running the ball the length of the pitch and scoring a converted try, but it was not to be as a knock-on quickly ended the move and the final whistle blew.
Success was particularly sweet for New Zealand-born Wallabies coach Robbie Deans and 111-cap skipper and lock Nathan Sharpe, who edged ahead of retired flank George Smith as the most capped Australian forward.
Deans has been under pressure after two defeats by New Zealand and heavy loss in South Africa last weekend, and injured flyhalf Quade Cooper added fuel to the fire by labelling the squad atmosphere "toxic".
Sharpe,a 34-year-old two-metre, 115-kilogram gentle giant of rugby, desperately wanted to leave the international scene on a high and he was part of a beefed-up pack that held their own against much vaunted opponents.
Harris kicked six penalties and a conversion with Ioane completing the scoring while Argentina flyhalf Juan Martin Hernandez slotted three penalties, Bosch one penalty and a conversion, and Imhoff scored a try.
Victory lifted Australia to second place – they finished level on 12 points with South Africa but won more matches – in the first four-nation southern hemisphere championship that was dominated by New Zealand with six wins.
The All Blacks recovered from a poor first half to outscore the Springboks by four tries to one in a 32-16 Soweto triumph that confirmed their status as the leading rugby nation.
Australia led 15-9 after a far from pretty first half that quickly developed into a battle of the boot between Harris, whose customary position is flyhalf, and Hernandez.
Harris landed his five attempts while Beale missed with a long range effort and after succeeding with his first three shots, Hernandez fluffed two for the home team, who had lock Patricio Albacete sin binned on 25 minutes.
The scrappy second half was equally hard on the eyes with many handling errors and a Bosch penalty narrowed the gap to 15-12 after he took over the kicking duties when a leg injury forced Hernandez to retire.
Ioane, one of the few first choices in a Wallaby team so hard hit by injuries this season that they have had four skippers, then turned the tide decisively in favour of the visiting team.
Australia beat Argentina twice, won and lost against South Africa and fell twice to New Zealand while Argentina, appearing in a major competition other than the World Cup for the first time, held South Africa at home and lost the rest.
Argentina – Try: Juan José Imhoff. Conversion: Marcelo Bosch. Penalties: Juan Martin Hernández (4)
Australia – Try: Digby Ioane. Conversion: Mike Harris. Penalties: Harris (6)