The win put South Africa in a strong position to claim the remaining spot from Group A, after England secured their berth, beating Sri Lanka by 26 runs on Monday — their fourth straight win in the Super 12 round.
England leads the table with eight points, followed by South Africa with six points. Australia got four points on the board but with two games left, they will give South Africa a run to grab the remaining semi-final spot from Group A.
Sri Lanka, with three losses, sits in fourth place in the points table, and even if they beat West Indies in their last group game on Thursday, they will have only four points on the board.
Sri Lanka won their first Super 12 game against Bangladesh but lost to Australia, South Africa and England in the next three games, which proved costly in the end.