Live: Australia chases victory as Durban Test approaches gripping finale

Markram adds another single to start the over, and Mulder is similarly in no hurry.

Too straight from over the wicket and Mulder just knocks one to deep fine leg.

Late in another pretty ineffectual over, Starc comes around the wicket and finds some swing but still too wide to bother the batters.

I assume telling him: “Step aside, son. Let me show you how it’s done.”

Wide and crushed through cover by Wiaan Mulder. It looks destined for the boundary, but Beau Webster does a brilliant job cleaning up on the rope. That was a superb effort, sliding in on his knees and tucking his feet in behind him, to keep it to two.

Shaun Pollock insists in commentary that this is a “team over” from Starc, aimed primarily at creating more footholes rather than just taking wickets.

Hilariously, he pulls out of a delivery late, meaning he gets a free couple of steps down the pitch outside a right-hander’s off stump.

Meanwhile Aiden Markram is leaving everything going across him.

How many overs will he get before Nathan Lyon subs in?

Aiden Markram clips through the leg side for two more. He’s working off his hip well.

Another single in the same fashion. There looks like a reluctance to hit against the spin, so Renshaw may need to get further outside off to find the spin and threaten both edges.

I didn’t mention it, but Steve Smith was at first slip for that first over. So whatever his issues were yesterday, he’s feeling better now.

Four! Mitchell Starc starts on the pads of Wiaan Mulder and he’s whipped away. Remember, he’s batting six but Mulder has a Test triple century.

Whoa, that’s a massive wide from Starc across the right-handed Mulder.

Mulder isn’t tempted outside off. Starc is off line but definitely loosening up the surface and adding to those footholes for the off spinners to aim at.

Shaun Pollock says Starc is even walking back to his mark a little closer than usual to the danger area, stressing it’s all perfectly legal.

This is much more wholesome ‘zoom and enhance’ camera work than the last time the Aussies were in South Africa.

The Man with the Golden Arm is going to bowl his off spinners to start the day’s play.

Aiden Markram is on strike, and immediately off strike as he gets back and works behind square leg.

Wiaan Mulder is defending well. Renshaw doing enough to draw him onto the front foot outside off.

And he bunts one down the ground for a single to close out the over.

And the flood lights are already on, which isn’t a great sign.

It looks like the clouds will linger, to varying levels of intensity, throughout day five.

We could well be poised for another early finish.

Early wickets the key for the Australians.

Well Christine, it will be a draw.

Every discussion about these early stumps calls have been tinged with a fear of what happens if it ends up robbing one team of a famous victory.

It was another incredibly professional display by the Australians once again yesterday and it has them set up for a comprehensive victory today.

Aiden Markram and Wiaan Mulder hold the keys for South Africa to cause an enormous upset, but there is still plenty of batting to come after them too.

Russell Jackson gives you the lay of the land…

The equations are pretty simple today:

• South Africa is 4-102 with Aiden Markram (45) and Wiaan Mulder (5) at the crease
• The Proteas are still 319 runs from an unlikely victory
• Australia needs six more wickets
• We are supposed to squeeze in 98 overs today

The only complicating factor will be whether light will cut the day short as it did on the first three days?