A toss won, but a game lost was the scene at Kingsmead on Sunday for a red-faced South African side, when Australia secured a clean sweep in the T20 format.

The hosts will next be hoping to find form in the all-important longer format of the white ball game, with the 50 over World Cup just one month away.

The Proteas batting has seen significant improvement since Wednesday's opener, as Aiden Markram elected to set a target.

The skipper got into the 40s alongside Reeza Hendricks and Donovan Ferreira; though Temba Bavuma struggled with his second duck of the series.

Markram's men managed to put up 190 runs on the board for the loss of eight wickets after 115 all out and 164/8 in the first two games.

The pitch appeared to create some uneven bounce as Sean Abbott took 4/31 in his four overs.

In the second period, though, the visitors looked comfortable with the bat -- as Travis Head smashed 91 off 48 at the top of the order while Marcus Stoinis (37) finished things off with two overs and five wickets to spare.

The Aussies looked calm and composed in their celebration, with captain Mitchell Marsh claiming the Man of the Series award.

The T20 series may now be behind them, but with the World Cup looming, the ODI games will be of utmost importance as both sides look to get into the groove ahead of the showpiece event.

The first of five one-dayers kicks off in Bloemfontein on Thursday.