Sri Lanka have withdrawn Isuru Udana, Thikshila de Silva, Seekkuge Prasanna from their squad to face the Proteas in a five match ODI series starting on January 28.
The trio will be replaced by seamers Lahiru Kumara and Vikum Sanjaya and leg spinner Jeffrey Vandersay.
The exclusion of Prasanna comes as something of a surprise given the vital role he played in the T20I series victory over South Africa.
Kumara was impressive during the Test series against South Africa where he bowled with good pace and was able to consistently trouble the Proteas batsmen.
Sanjaya was also in the group for the Tests although he was not handed what would have been his Test debut.
Vandersay played two of the ODIs in the triangular series in Zimbabwe although one of those matches was rained off before he could bowl a ball. He took 3 for 50 in ten overs in the other.
The leg-spinner took a ten-wicket haul in his most recent first class match in Sri Lanka's Premier League Tournament.
While Vandersay is arguably a better bowler than Prasanna he offers significantly less with the willow in hand.
Upul Tharanga will lead the squad in the absence of injured skipper Angelo Mathews
Sri Lanka ODI squad: Upul Tharanga (capt), Dinesh Chandimal (wk), Dhananjaya Silva, Niroshan Dickwella, Sandun Weerakkody, Kusal Mendis, Asela Gunaratne, Chathuranga de Silva, Sachith Pathirana, Jeffrey Vandersay, Lakshan Sandakan, Lahiru Madushanka, Nuwan Kulasekara, Lahiru Kumara, Suranga Lakmal, Vikum Sanjaya.