A century from Rilee Rossouw and a pair of game-changing wickets from Imran Tahir saw South Africa secure a 31-run win at Newlands to become the first team to whitewash Australia in a five-match one-day international series.

The Proteas were set on their way to an historic 5-0 victory by Rossouw's outstanding 122, the batsman showing exactly why he has earned a maiden call-up to the Test squad for next month's series in Australia.

Rossouw built a formidable 178-run partnership with JP Duminy (73), the highest fourth-wicket stand in an ODI on this ground, to propel the hosts to 327-8.

Australia's chase began positively until Tahir (2-42), back in the line-up after being rested for the fourth match in Port Elizabeth, removed Aaron Finch (19) and captain Steve Smith (0) in the same over.

David Warner was left to fight a solitary battle in his attempt to get the tourists over the line, but his phenomenal 136-ball 173 - the highest score by an Australian batsman in an ODI against South Africa - proved to be in vain.

The Proteas appeared to be in trouble with the dismissals of Quinton de Kock (12), Hashim Amla (25) and skipper Faf du Plessis (11), the latter pair accounted for by Joe Mennie (3-49), leaving them at 52-3 after 11 overs.

But Rossouw and Duminy hauled them back on track, setting the tone by combining to plunder 17 runs off the first over from Mitchell Marsh (0-53).

Duminy struck a four through mid-on to make it a record fourth-wicket stand at Newlands, but he was caught at backward point off Mennie three balls before Rossouw brought up his third ODI ton.

Rossouw, strong through the covers and down the ground, continued to search for boundaries and holed out to long-on off Chris Tremain (3-64) , but David Miller (39) kept pushing on to set an imposing total.

Finch and Warner earned reprieves when they were dropped off Kagiso Rabada (2-84) during the early stages of Australia's response, but Tahir finally made the breakthrough in the 14th over.

The spinner bowled Finch to end a 72-run opening stand and added the scalp of Smith two balls later, turning the tide and severely denting the tourists' response of avoiding the clean sweep.

Warner was unrelenting and brought up his ninth ODI hundred off 88 balls with a single after guiding to mid-on, but his celebrations were subdued with victory already looking out of reach.

Having been let down by the fielders, Rabada took matters into his own hands by knocking off the bails of Marsh (35), while Warner's sensational effort, which included 24 boundaries, was brought to an end when Tahir's pinpoint throw enabled De Kock to finish the run out.

Australia will now attempt to recover some of their pride when they host South Africa for a three-match Test series that begins in Perth on November 3.