Markram is into the team at No. 3 after a run of strong form in domestic cricket improved his chances of making the squad for the 50-over World Cup in England and Wales, which starts in two months. Hashim Amla, who was expected to return to the team, is unavailable for the last two games of the series because of a family illness.
Sri Lanka gave an international debut to batsman Priyamal Perera while ambidextrous spin bowler Kamindu Mendis retains his place. Mendis has the unusual ability to bowl with both his right and left arm and switches between the two regularly.
South Africa has an unassailable 3-0 lead in the five-match series.
South Africa: Reeza Hendricks, Quinton de Kock, Aiden Markram, Faf du Plessis (captain), David Miller, JP Duminy, Andile Phehlukwayo, Dale Steyn, Anrich Nortje, Lungi Ngidi, Tabraiz Shamsi.
Sri Lanka: Upul Tharanga, Avishka Fernando, Oshada Fernando, Priyamal Perera, Kusal Mendis, Dhananjaya de Silva, Kamindu Mendis, Thisara Perera, Lasith Malinga (captain), Isuru Udana, Kasun Rajitha.
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