South Africa won the toss and decided to bowl in the decisive final one-day international against Pakistan on Wednesday.
The match at Newlands is a series decider with both teams having won twice in the first four games.
South Africa made two changes from the side beaten by eight wickets in Johannesburg on Sunday, bringing in all-rounders Wiaan Mulder and Dwaine Pretorius for batsman David Miller and fast bowler Beuran Hendricks.
Mulder was a late addition to the squad after missing most of the season because of injury.
“We want to look at our all-rounders and see how they respond in this sort of situation,” said South African captain Faf du Plessis.
Pakistan were unchanged.
Stand-in captain Shoaib Malik said he was happy to bat first in what is effectively a final.
“It is a big game and if you put a score on the board it puts your opponents under pressure,” he said.
South Africa: Faf du Plessis (captain), Hashim Amla, Quinton de Kock (wkt), Reeza Hendricks, Rassie van der Dussen, Wiaan Mulder, Dwaine Pretorius, Andile Phehlukwayo, Kagiso Rabada, Dale Steyn, Imran Tahir.
Pakistan: Shoaib Malik (captain), Imam-ul-Haq, Fakhar Zaman, Babar Azam, Mohammad Hafeez, Mohammad Rizwan (wkt), Shadab Khan, Imad Wasim, Mohammad Amir, Usman Shinwari, Shaheen Shah Afridi.
Umpires: Gregory Brathwaite (WIN), Adrian Holdstock (RSA),
TV umpire: Paul Reiffel (AUS)
Match referee: Ranjan Madugalle (SRI)