South Africa were 140 for four in their second innings at the close, 40 runs ahead with six wickets remaining.

Starc, who took six for 72 in the first innings, again struck crucial blows, dismissing Aiden Markram and Marques Ackerman before South Africa had erased their first innings deficit.

Off-spinner Nathan Lyon bowled South African captain Temba Bavuma for 35 in the penultimate over of the day to plunge the world Test champions into deep trouble.

Josh Inglis earlier completed his second Test century before Australia were bowled out for 429 after starting the day on 330 for four.

Starting the second innings 100 runs behind, South Africa made a poor start when Markram was out for one, driving Starc to mid-off.

David Bedingham fell to a hook shot for the second time in the match, caught at deep backward square leg off Josh Hazlewood for 11.

As in his first innings of 95, the left-handed Ackerman went for his shots. He and Bavuma had a third wicket stand of 64 but South Africa still trailed by five runs when Starc produced a vicious bouncer to dismiss Ackerman for 62, caught at gully off bat and helmet.

Australia earlier lost their remaining six first innings wickets for 99 runs.

Inglis made 102 – the same score he had made on debut against Sri Lanka two seasons ago – and shared a partnership of 185 for the fifth wicket with Alex Carey (80), with the pair adding 40 runs to the overnight total.

Inglis reached his century off 132 balls when he reverse-swept off-spinner Simon Harmer for four but he was caught behind off the same bowler three balls later.

Carey was caught at slip off Harmer four overs later.