Stumps South Africa 149 for 6 (Zondo 39, Cummins 3-29, Hazlewood 2-29) trail Australia 475 for 4 dec (Khawaja 195*, Smith 104, Labuschagne 79, Head 70, Nortje 2-55) by 326 runs
Australia quick Pat Cummins tormented South Africa with a sensational spell late on day four as the continued their bold push for a third Test victory at the SCG.
At stumps, South Africa were still well short of the follow-on target after Cummins' earlier declaration of Australia's first innings. Four straight sessions had been lost due to rain, but Australia still believe they can secure a series sweep to book a spot in the World Test Championship final in June.
Cummins fuelled their hope with the late wickets of Khaya Zondo and Kyle Verreynne to leave South Africa nervously placed with 98 overs to be bowled on day five. There is only a small chance of rain forecast in Sydney for Sunday.
Amid gloomy conditions, Cummins produced an outstanding spell marked by inconsistent bounce from around the wicket. Having threatened with the short ball, Cummins bowled a gem of a full delivery to trap Zondo lbw for 39 after the batter unsuccessfully reviewed the decision.
He almost replicated the delivery to Marco Jansen but the ball pitched outside the leg stump before hitting the pads. Looking like taking a wicket on almost every ball, spurred on by an enthusiastic crowd, Cummins from over the wicket had Verreynne caught at slip after producing a perfect length delivery.
He had earlier picked up recalled batter Heinrich Klaasen, whose only previous Test match was against India in 2019, with a nasty short delivery that was gloved to wicketkeeper Alex Carey.
A pumped-up Josh Hazlewood also starred with the wickets of skipper Dean Elgar and Temba Bavuma. Having been preferred over Scott Boland, Hazlewood repaid the faith of the selectors on his return after suffering a side strain against West Indies in the opening Test of the home season.
He troubled Elgar in particular with vicious short-pitched deliveries, and eventually hit his glove to be caught behind. Elgar has only mustered 46 runs in five innings during a wretched series. He had survived a contentious low catch at slip after edging Hazlewood to Steven Smith, who flung out his right hand in a spectacular effort, but it was given not out on the soft signal.
Initial replays seemingly showed the ball going straight into a full-flung Smith's right hand. But further replays cast doubt over whether some of the ball brushed the turf and it was enough for third umpire Richard Kettleborough to uphold the not-out decision.
It was consistent with Kettleborough's decision-making - on day one, when Marnus Labuschagne edged to first slip where Simon Harmer claimed a low catch but replays proved inconclusive, Kettleborough had decided in favour of the batter too.
Hazlewood in the final session dismissed Bavuma, who tamely edged a length delivery to end what had been a promising innings. He played aggressively at times and struck spinner Nathan Lyon for a couple of sixes before tea, but was left despondent after his dismissal for 35.
Left-arm spinner Ashton Agar bowled just seven overs and failed to threaten in his first Test match since 2017, and his first in Australia.
Cummins' declaration after lunch meant opener Usman Khawaja remained stuck on his highest Test score of 195. Frank Worrell and Sachin Tendulkar are the only other batters apart from Khawaja to have been in the 190s when their captains declared an innings closed.
Matthew Renshaw was on 5 in his first Test match since 2018, after having tested positive for Covid-19 before play on day one. He returned negative rapid antigen tests yesterday and this morning.
There was a pre-match ceremony dedicated to Glenn McGrath's late wife, Jane, who died of breast cancer in 2008. It is traditionally held on day three but was moved because of the weather, and players from both teams were presented with pink caps.
