South Africa's top-order batsman Hashim Amla is struggling to be fit for the next two one-day internationals in Sri Lanka after suffering a groin strain in Tuesday's defeat by the home side.
"Amla fell awkwardly while fielding on the boundary and was immediately taken to the hospital for a scan," said team manager Mohammed Moosajee on Wednesday.
"He was assessed to have a Grade 1 strain to the left groin muscle.
Amla missed the first ODI on Saturday with a stiff neck. He had been due to open on Tuesday before being injured in the rain-hit game.
The third and fourth ODIs take place in Kandy on July 26 and 28.
Sri Lanka lead the series 2-0 and Angelo Mathews now returns as captain after missing the first two games.
The ICC banned him for two matches for maintaining a slow over rate during the West Indies' Tri-Nation Series final against India this month.
Image: Hashim Amla
SL beat Proteas by D/L method, take 2-0 lead in ODI serIes
Test rankings: 6th place Pujara highest ranked Indian batsman
Sangakkara century leads Sri Lanka to stunning win
Steyn rested for South Africa's limited overs tour of SL
Turning point: Early breakthroughs turn it England's way