Dinesh Chandimal will become Sri Lanka's youngest ODI captain, at 23, after being handed the reins for the first two matches against South Africa in Colombo. Regular captain Angelo Mathews was unavailable after earning a two-match suspension for an over-rate offence in the West Indies tri-nation series. Lahiru Thirimanne was named vice-captain.

Middle-order batsman Jehan Mubarak earned a recall, four years after his last international appearance. Now 32, Mubarak did not show sustained aptitude at the top level in his previous stints with the national team, despite a fine domestic reputation. He hit 42 in the practice match against the South Africans on Wednesday and had been the top-scorer in Sri Lanka's inter-provincial List A competition in January, with an average of 60 and a strike rate of 120.96. Uncapped middle-order batsman Angelo Perera was named in the 15-man squad as well, after top-scoring for his side in the warm-up match, with 46.

Allrounder Thisara Perera reclaimed his place after missing the West Indies tri-series. An injury to Nuwan Kulasekara's left ring finger, which was sustained in the Caribbean, ruled him out of the first two matches and Suranga Lakmal retained his place as Kulasekara's replacement. Tillakaratne Dilshan is also recovering from a tear to his right medial calf muscle, but was named in the squad and is expected to be fit for the first match. Upul Tharanga, who hit a career-best 174 not out in the West Indies after being picked as Dilshan's replacement, was also retained, at the expense of Kusal Perera, who opened for Sri Lanka in the Champions Trophy.

Ajantha Mendis kept his place as well, despite having played just one match in the tri-series, but will compete with left-arm spinner Rangana Herath and offspinner Sachithra Senanayake for a place in the XI. Sri Lanka also have part-time spin options in Mubarak and Angelo Perera, but legspinning allrounder Jeevan Mendis was omitted, after an unconvincing run.

Both matches will be played at the R Premadasa Stadium, but the squad may be changed ahead of the third ODI in Pallekele on July 26. The teams play five ODIs and three Twenty20s.

Andrew Fidel Fernando is ESPNcricinfo's Sri Lanka correspondent. He tweets here