Cape Town - Proteas skipper Quinton de Kock has won the toss decided to bowl first in the first T20 International against Australia at the Wanderers on Friday evening.
"There's a bit of weather around and batting does get easier later in the night," said De Kock.
Former captain Faf du Plessis and fast bowler Kagiso Rabada returned for the home team after being rested during one-day and T20 series against England.
"They bring a lot of impetus to our team," said De Kock.
Batsman Pite van Biljon was set to make his debut after Heinrich Klaasen, South Africa's top-scorer in the final T20 international against England last Sunday, was injured during the pre-match warm-up.
The game is the first in South Africa for Steve Smith and David Warner since March 2018 when they were banned for ball-tampering in the third Test in Cape Town.
Smith was Australia captain and Warner his deputy at the time.
Australian captain Aaron Finch said he would also have bowled if he had won the toss.
"It's a bit tacky on top so there might be a bit there early," he said of the pitch. "But (batting or bowling) doesn't make much difference."
An open wooden stand on the eastern side of the ground was closed for safety reasons after heavy recent rain.
Although all tickets for the match had been sold in advance, Jono Leaf-Wright, chief executive of the host Central Gauteng union, said spectators who had bought tickets in that area would be accommodated elsewhere.
South Africa: Quinton de Kock (captain, wkt), Rassie van der Dussen, Faf du Plessis, Jon-Jon Smuts, David Miller, Pite van Biljon, Andile Phehlukwayo, Dale Steyn, Kagiso Rabada, Lungi Ngidi, Tabraiz Shamsi.
Australia: Aaron Finch (capt), David Warner, Steve Smith, Matthew Wade, Mitchell Marsh, Alex Carey (wkt), Ashton Agar, Pat Cummins, Mitchell Starc, Kane Richardson, Adam Zampa.
Umpires: Adrian Holdstock, Allahudien Palekar (both RSA)
TV umpire: Bongani Jele (RSA)