Australia bowled out for 177 to lose by 134 runs - heaviest World Cup defeat by runs
Stoinis given out caught behind on review but ball appeared to flick glove that was off the bat
Smith given out lbw on review - batter felt ball was missing leg stump
South Africa post 311-7 - De Kock 109 (106), Markram 56 (43); Maxwell 2-34
De Kock hits second century in as many matches
Sloppy Australia drop five catches, with Zampa also failing to get to chance
Steven Finn
Former England bowler on BBC Test Match Special
It is remarkable that went for six. It wasn't a ramp like you'd see Jos Buttler play, it was more like a flick but it cleared fine leg.
Geoff Lemon
BBC Test Match Special commentator
Mitchell Marsh was back-pedalling for that first six and hoping it was a catching chance but it just cleared him. Even if he had his heels on the ropes I don't think it would have been a catch.
After facing a maiden in the previous over Quinton de Kock gets the run rate ticking again.
He walks across his stumps to the penultimate ball of Josh Hazlewood's fifth over and effortlessly flicks it square for six.
The final ball of the over also disappears over the boundary but this is infinitely more brutal as he rocks on to the back foot and gives it the full treatement.
Glenn Maxwell, still with the sharpness of his pre-World Cup haircut, rattles through a maiden over - Australia's first of the match.
The spinner he refuses to allow Quinton de Kock any time to settle.
Phil Long
BBC Test Match Special statistician
Rassie van der Dussen has the fourth best average of anyone to play 20+ one-day internationals. He averages 58.29, with England's Dawid Malan (63.15), India's Shubman Gill (66.10) and the Netherlands' Ryan ten Doeschate (67) above him.
Two dots from Josh Hazlewood before an almighty swipe from Quinton de Kock, but it's a fresh air shot from the South African opener.
Next ball De Kock cuts it down to third for a single leaving Rassie van der Dussen to block out the last couple of deliverie.
Van der Dussen sporting some fetching bright green spikes, by the way.
Steven Finn
Former England bowler on BBC Test Match Special
Rassie van der Dussen will look to build an innings and take his time but he is a mighty fine player.
Thanks, Sam. Enjoy your brew.
Australia have been quite sloppy in the first 20 overs. South Africa will be the happier of the two teams you sense. There could be some fireworks if South Africa's explosive middle order get going here.
Josh Hazlewood returns for the Aussies.
Rassie van der Dussen is the new batter and he sees off the last couple of deliveries of the Glenn Maxwell over.
We're 20 overs into the innings and that means it's time for our first change of the day. I'm off for a cuppa and will leave you in the capable hands of Timothy Abraham.
Steven Finn
Former England bowler on BBC Test Match Special
It is a big boundary out there compared to some in India and Temba Bavuma backed himself to clear them but he can't do it. He was tied down by Australia. It almost a 'hit out or get out' situation for him.
Geoff Lemon
BBC Test Match Special commentator
Glenn Maxwell is roaring like a lion!
Bavuma c Warner b Maxwell 35 (SA 108-1)
Glenn Maxwell returns and makes the breakthrough!
Temba Bavuma was trying to clear the deep mid-wicket boundary but didn't get all of it.
The ball went high into the leg side and David Warner is underneath it to take the catch.
Australia needed that.
Aaron Finch
Former Australia captain on BBC Test Match Special
It feels like Adam Zampa has controlled his length a little better today. One of his great strengths, and why he's been one of the best bowlers in the world over the last four years, is that he's able to hit the top of the stumps consistently. He was a little wide against India in the opening game.
Five singles from Adam Zampa's latest.
South Africa don't need to force things at the moment and respect the Australia leg-spinner as he lands it nicely this time.
Temba Bavuma is still there for South Africa but he's had plenty of good fortune so far.
Here is the third chance he gave but Australia failed to take it...
Tidy over for Marcus Stoinis, just three singles from it as Temba Bavuma misses with an attempted pull shot to end the over.
Aaron Finch
Former Australia captain on BBC Test Match Special
Australia can almost be ultra-defensive to Quinton de Kock, he is looking really dangerous and like he wants to face a lot of balls.
Sometimes you have to look at it tactically and think about who you'd rather bowl at. They need to try and get a few dot balls and bowl at Temba Bevuma and then that might bring a reckless shot from Quinton de Kock.
Australia just haven't been able to do that yet.
Jonathan Agnew
BBC cricket correspondent on Test Match Special
This is just the start that South Africa will have wanted. We've got a good contest unfolding.
Three dot balls to end the over help Adam Zampa limit the damage, nine from it.
Australia are in real need of a wicket, though, with South Africa setting things up nicely for a big push in the second half of the innings.
Aaron Finch
Former Australia captain on BBC Test Match Special
The impact of playing one reserve sweep means that Australia will have to change their tact to Quinton de Kock.