Dewald Brevis made a much anticipated international debut for South Africa as one of two new caps in their T20I XI.
South Africa also welcomed back former captain Temba Bavuma, who was dropped after the T20 World Cup.
He is set to open the batting with Reeza Hendricks. Tristan Stubbs was inserted into the middle order and will keep wicket for the first time at international level.
The hosts are in experimental mode, so are their visitors. Australia had to make a last-minute change to their XI after Adam Zampa was forced out with illness. Legsponner Tanveer Sangha became the fourth newcomer in their team after Matthew Short, Aaron Hardie and Spencer Johnson were confirmed to make their debuts.
Mitchell Marsh, in his first match as a senior international captain, said he would have liked to bowl first but was happy to set South Africa a total.
South Africa: 1 Temba Bavuma, 2 Reeza Hendricks, 3 Rassie van der Dussen, 4 Aiden Markram (capt), 5 Dewald Brevis, 6 Tristan Stubbs (wk), 7 Marco Jansen, 8 Gerald Coetzee, 9 Lungi Ngidi, 10 Lizaad Williams, 11 Tabraiz Shamsi
Australia: 1 Matthew Short, 2 Travis Head, 3 Mitchell Marsh (capt), 4 Josh Inglis (wk), 5 Marcus Stoinis, 6 Tim David, 7 Aaron Hardie, 8 Sean Abbott, 9 Nathan Ellis, 10 Tanveer Sangha, 11 Spencer Johnson