South Africa 206 for 1 (Du Plessis 96*, Amla 80*) beat Sri Lanka 204 (Pretorius 3-25, Morris 3-46) by nine wickets
Chester-le-Street: Sri Lanka's hopes of reaching the World Cup semi-finals were dented as South Africa thrashed them by nine wickets at Chester-le-Street on Friday.
Victory would have taken Sri Lanka level on points with fourth-placed England, but they stay in seventh.
No player scored more than 30 as they were bowled out for a turgid 230 in the final over of their innings.
South Africa completed the win in 37.2 overs with Faf du Plessis making 96 not out and Hashim Amla an unbeaten 80.
The Proteas were already eliminated going into the match, and this was just their second victory in the competition.
Sri Lanka remain two points behind England and still have two matches remaining.
The biggest threats to England's top-four place are now likely to be Pakistan and Bangladesh, with the former playing Afghanistan on Saturday.