Ashwell Prince was appointed South Africa's first black cricket captain on Wednesday. Prince, 28, has played 21 tests and 37 one-day internationals. The middle-order batsman has a test average of 37.55, with four centuries. He captains the Western Cape Cobras in South Africa's provincial competition.
He replaces Graeme Smith who was ruled out of the two Tests in Sri Lanka, starting July 27.
Smith "will undergo a further stress X-ray later on Wednesday (Wednesday) with an ankle specialist to determine the full extent of his injury and the treatment required," a statement from Cricket South Africa said.
Smith damaged ankle ligaments while running in training last weekend. South Africa's regular vice-captain Jacques Kallis is also out of action as he recuperates from elbow surgery. South Africa also plays a triangular one-day tournament with hosts Sri Lanka and India, starting August 14.
Prince has been appointed captain for the Tests only. The limited-overs squad and captain will be named after the first test. South Africa's veteran allrounder Shaun Pollock will miss the first Test, remaining in the country with his wife for the birth of their second child.