South Africa 311 for 7 (de Kock 109, Markram 56, Maxwell 2-34) beat Australia 177 (Labuschagne 46, Rabada 3-33) by 134 runs
Lucknow: Australia suffered their heaviest World Cup defeat as they were trounced by South Africa in Lucknow on Thursday.
They were set 312 to win but a miserable batting display saw them bowled out for 177 in 40.5 overs to lose by 134 runs.
It means they have lost their opening two games and four consecutive World Cup matches for the first time.
South Africa posted 311-7, with Quinton de Kock hitting 109 for his second century of the tournament.
He joins compatriot AB de Villiers as the only batter to start a Men's World Cup with consecutive hundreds.
Australia's next game is against Sri Lanka on Monday, while South Africa play the Netherlands on Tuesday.
Friday's World Cup action sees New Zealand, who have won their first two games, face Bangladesh in Chennai.