Australia’s mix of seam and spin bowling flummoxed South Africa as they limped to 128 for seven after being sent in to bat.
Left-arm paceman Mitchell Starc immediately backed up Australia’s decision to field first as he bowled a maiden over first up and struck Quinton de Kock in the throat, before trapping Hashim Amla lbw for two in his second over.
Starc returned later to bowl Albie Morkel, who had briefly thrilled his home crowd with two sixes in his 18, with a brilliant yorker and was Australia’s most impressive bowler with an outstanding two for 16 in his four overs.
Spinners Glenn Maxwell and Brad Hogg were Australia’s other most successful bowlers with two wickets apiece.
De Kock was the one South African batsman to show some quality on a slowish pitch as he scored 41 off 40 balls before wrist-spinner Hogg ripped a delivery across him to have the left-hander caught behind.
South Africa, who leave on Saturday for the ICC World T20, will be concerned by their poor batting display, especially the quantity of balls hit straight to fielders.
Faf du Plessis (5), JP Duminy (13), AB de Villiers (11) and David Miller (2) were all dismissed in soft fashion as they stupidly picked out fielders with lofted strokes.
Tailenders Wayne Parnell (17*) and Beuran Hendricks (12*) spared some of the home team’s blushes as they added 25 for the eighth wicket in the last three-and-a-half overs.
Australia made an aggressive start to their run-chase as openers Aaron Finch and Cameron White (14) added 43 off 29 balls to leave a capacity crowd resigned to defeat.
Finch was not afraid to go the aerial route as he belted 39 off 27 balls and Shane Watson scored 35 off 28 balls as Australia cruised to victory.
South Africa had few ways of getting back into the contest, but leg-spinner Imran Tahir was their most effective option, taking two for 21 in his four overs, but his batsmen had left him with far too much work to do.
The home side were left to rue the rain disappearing from Gauteng as Australia dealt a heavy blow to their World T20 plans.