Mitchell Starc blitzed the Proteas tail late on day one to give his batting line-up the perfect chance to shine on day two.
But can they make it count?
Follow the action with our live blog.
Proteas problem
This is becoming a small issue for South Africa.
They are bowling far to short.
They have not given the ball a chance to swing and we’ve seen no movement at all.
They have had to put a deep point out for Head to stop the boundaries and he is using it to get cheap, risk-free singles.
He also times it better when he knows it’s only going to be a single anyway.
AUS 0-27
Calm start
Australia will be happy with the quiet start here.
Anything wide is going to the rope but otherwise, Renshaw and Head have been smart.
The crowd is very quiet which is a win.
AUS 0-25
Square up
Jansen squares Renshaw up but the edge runs away for four backward of point.
The South Africans have been a touch too short so far but the Aussies have been leaving well.
AUS 0-11
Top start
Jansen challenges both edges in his first over but Renshaw sees it through.
Head will get his first ball now and gets off the mark with a chunky inside edge out to square leg.
AUS 0-7
Away we go!
Rabada had four balls over the wicket before switching to around.
But he floats up a juicy full toss and Renshaw cashes in with a boundary.
He then rotates the strike.
AUS 0-5
Players ready
The teams are out in the middle and we are about to get underway.
Rabada will open the bowling with Head and Renshaw to face the music.
Smith fallout
Reports have emerged the Aussies were not happy when Steve Smith decided to rule himself out with a neck injury before play yesterday.
Reminder
The Australians have a very different looking batting order for this Test so this is how it’s shaping up.
Travis Head
Matt Renshaw
Marnus Labuschagne
Cam Green
Josh Inglis
Cooper Connolly
Pat Cummins
Mitchell Starc
Nathan Lyon
Josh Hazlewood
Welcome!
Not to understate anything, but this could be the day that decides the series.
South Africa didn’t make the most of their good position yesterday but still posted 329.
Australia will want to get well passed that to feel comfortable, somewhere around the 450 mark.
But they will have their work cut out against South Africa’s quicks.
A failure from the batters today will make it all but impossible for the tourists to win.
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