Sydney - James Faulkner has hit the winning boundary with five balls to spare to give Australia a thrilling two-wicket victory over South Africa on Sunday and push them to the top of the ICC one-day rankings.
As it happened: Australia v Proteas
The Australians were cruising towards a rain-reduced victory target of 275 in Sydney but then lost four wickets for three runs to give the Proteas a late chance of victory.
But Faulkner (six not out) got Australia over the line with a sweep for four off spinner Robin Peterson, who had bowled the Proteas into contention with four wickets.
Australia secured a 4-1 series win and nudged ahead of India by just 0.2 points to top the one-day rankings, less than three months before the start of the World Cup in Australia and New Zealand.
Wicketkeeper Quinton de Kock was named man-of-the-match in a losing side for his 107 off 123 balls after South Africa won the toss and scored 280 for six.
The Australians seemed in control of the run chase with Aaron Finch scoring 76 (67 balls), Shane Watson 82 (93 balls) and man of the series Steve Smith 67 (74 balls).
But some reckless batting coupled with Peterson's mesmerising spin brought South Africa back into contention after the loss of Glenn Maxwell, Smith, skipper George Bailey, Matt Wade and Pat Cummins.
Faulkner got the Australians home in the final over.
"We made it a bit difficult for ourselves in the end and Jimmy (Faulkner) again got us home so it's nice to win the series 4-1," Smith said.
"We were a bit nervous sitting and watching and we were actually feeling a little bit sick, I don't know what happened, and luckily Jimmy came out and rescued us again."
The South Africans never gave in. Coupled with Peterson's bowling, Rilee Rossouw took four catches, including a sprawling effort to dismiss Smith in the outfield at a pivotal time in the match.
Proteas skipper AB De Villiers, who missed the final game with injured ribs, said his side was hurting after losing the series by such a wide margin and his bowlers needed to improve their discipline.
Ten no-balls over the course of the series cost them dearly.
De Villiers wants the problem cleared up before the start of the World Cup.
"It's unacceptable and it shouldn't happen -- it's not good enough," he said.
In the absence of de Villiers, de Kock stepped up to play a valuable innings for the Proteas, who were striving to avoid a fourth defeat in the five-game ODI series.
The wicketkeeper's 107 off 123 balls with 14 fours was his sixth ODI hundred but first against Australia.
It was also the first one-day century by a South African at the Sydney Cricket Ground.
De Kock survived a close shave on 98 as Smith's throw narrowly missed the stumps when the batsman was well out of hi ground.
He went on to reach his century before being caught off his glove going for a uppercut off paceman Pat Cummins in the 41st over.
De Kock put on 107 for the second wicket with Rossouw, who scored 51 off 71 balls.
Farhaan Behardien provided late fireworks in his best knock of the series with 63 off 41 balls, including seven fours and two sixes.
He looked set for a third six only to be athletically caught above his head by Smith on the boundary rope.
Cummins was the best Australian bowler with three for 54.
Australia now have a four-Test home series against India before hosting a triangular ODI series featuring world champions India and England from January 16 to February 1, ahead of the World Cup.
Australia: AJ Finch, DA Warner, SR Watson, SPD Smith, GJ Bailey (captain), GJ Maxwell, MS Wade (wicketkeeper), JP Faulkner, PJ Cummins, JR Hazlewood, MA Starc
South Africa: Q de Kock (wicketkeeper), HM Amla (captain), F du Plessis, RR Rossouw, DA Miller, F Behardien, R McLaren, RJ Peterson, WD Parnell, M Morkel, KJ Abbott