Image source, Getty Images

Just one day remains of an enthralling Test series and it promises to be a thriller.

South Africa will go in as favourites but they still need 10 wickets on a fairly docile surface, Australia need 288 to win.

Few would have expected that at the start of day four as the Proteas resumed on 140-4, leading by just 40.

But they battled hard in the morning session through Ryan Rickelton and Matthew Breetzke and gradually grew the lead.

Breetzke fell half an hour before lunch but that was Australia's only wicket of the first two session as Rickelton and Wiaan Mulder produced a potentially match-winning stand of 154.

Rickelton reached an excellent century but was run out soon after as the tourists hit back, taking 4-17 to put some pressure back on South Africa.

However, Mulder remained and, with the support of number 11 Kagiso Rabada, boost the hosts total and reached a superb hundred in the process.

His wicket in the last over of the day brought play to a close.

One day to go. Advantage South Africa? Join us tomorrow morning for 08:25 GMT for what promises to be quite the final day.

WinViz has South Africa as clear favourites but Australia, at 30%, cannot be written off.

What a day we have in store tomorrow at Newlands.

Image source, BBC Sport/CricViz

That is certainly one of the subplots going into day five, Will.

If ever there was a time to rediscover your best form, in the fourth innings chasing a tricky total against the World Test champions might just be it.

Whether Marnus Labuschagne can do that remains to be seen.

So after memorable centuries for Ryan Rickelton and Wiaan Mulder, it's South Africa heading into day five with their noses in front.

What a Test match it has been in Cape Town with the series on the line. Australia need 288 to win, South Africa need 10 wickets.

A couple of violent shots from Wiaan Mulder off Pat Cummins but he can't find the gaps in the deep.

Two dot balls. Four left in the day.

Just a single from the rest of the over. Time for one more over before stumps.

What a day it's been for the Proteas. Right up against it this morning, they'll head into day five as favourites to win the series.

SA 386-9published at 133.1 overs

133.1 overs

Lead by 286

Six more!

Wiaan Mulder has gone into T20 mode! He nails a slog-sweep off Nathan Lyon over deep backward square and onto the grass bank.

Big runs for South Africa.

SA 380-9published at 133 overs

133 overs

Lead by 280

Hammered over the ropes for six!

Wiaan Mulder middles a pull shot off Pat Cummins for his third maximum!

The century-maker adds a single next ball and KG Rabada ducks the last.

Time for a couple more overs. You can't imagine South Africa will bat on tomorrow so is there where Mulder goes into T20 mode?

Pat Cummins overcooks a bouncer and that's called wide just as the clock ticks past 10 to the hour.

That means Australia will definitely not bat today. Who would have thought that could happen at the start of the day?

Temba Bavuma wasn't in his whites when the TV showed him in the dressing room and Wiaan Mulder isn't really looking to go on the attack too much since reaching his ton.

No declaration tonight then, it would seem.

A works a single from the fifth ball and Kagiso Rabada slaps Nathan Lyon's last out to deep cover. No run taken.

100 for Wiaan Mulderpublished at 131.1 overs

131.1 overs

SA 371-9 | Lead by 271

Wiaan Mulder punches the air!

He goes to his fourth Test century from 204 balls - what an innings and what a time to play it!

A firm drive through the covers gets him there, finding the gap and he's able to get back for two.

98 for Wiaan Mulder.

Two more balls for KG Rabada to keep out... and he does so once more.

Have we reached the point where the Australia openers might be quite happy if this last wicket doesn't fall in the next few minutes?

Another roar from the crowd as Kagiso Rabada sees out the over.

At most, South Africa are going to have 10 minutes to go at the Australia openers.

The crowd are more bothered about Wiaan Mulder and a potential century for now, though...

Over to you again, KG.

Two more balls for the number 11 to survive against Nathan Lyon.

Wiaan Mulder will watch on nervously, three shy of a ton.

KG Rabada again negotiates the last couple of balls of an over to give Wiaan Mulder the strike for the start of the next.

Mulder is four short of a fourth Test hundred...

It's not all been great, Tom, I'll give you that but they did have to think about trying to win the match and if they were just going to bat on, not scoring all that quickly, was that of much more benefit?

Anyway, Wiaan Mulder is doing his bit to boost the lead now, pulling Pat Cummins for four to move to 95...