Thikshila de Silva is in line for an international debut after being included in Sri Lanka's squad for three Twenty20s against South Africa.
The batting all-rounder is part of a 15-man selection, as is Lakshan Sandakan, who has featured in three Tests and a one-day international, but is yet to make his T20 bow.
Seekkuge Prasanna gets the nod over Jeffrey Vandersay, while seam bowlers Isuru Udana and Nuwan Kulasekara have been given recalls.
So far it has been an unhappy tour for Sri Lanka, who lost the opening two Test matches by 206 and 282 runs, with the final five-day meeting beginning at the Wanderers on Thursday.
The three-match T20 series starts at Centurion on January 20.
Sri Lanka Twenty20 squad:
Angelo Mathews, Dinesh Chandimal, Danushka Gunathilaka, Seekkuge Prasanna, Niroshan Dickwella, Suranga Lakmal, Nuwan Pradeep, Isuru Udana, Kusal Mendis, Dhananjaya Silva, Asela Gunarathna, Sachith Pathirana, Lakshan Sadakan, Thikshila de Silva, Nuwan Kulasekara.