Truth be told, this much-hyped series between these top-ranked Test nations hasn't quite yet reached dizzying heights but it could be set for a thrilling conclusion. While highly unpredictable - with the winners of each Test required to dig out of major early holes with the bat - the end results have been ultimately lopsided.

Both teams have endured a dud. South Africa were shaking off the cobwebs at Kingsmead after almost a year's break from Test cricket, while Australia's head-scratcher at St George's Park was surely one of their worst performances under Pat Cummins.

Both Tests teased nerve-jangling finishes but ultimately fell well short. The atmosphere has been subdued with crowds sparse, for a variety of reasons, and - for better or worse - the hostility that has often marked these fiery contests has mostly been absent. Bad light in Durban and rain in Gqeberha did not help.

Yet, despite all that, it's perfectly set up for a mouth-watering finale in Cape Town, where an under-pressure Australia face the ghosts of the past but are very much focused on fixing ongoing problems.

Australia are in the early stages of a marathon Test run, with much of the spotlight on breaking long droughts in India and England - likely the final chance for many in this ageing side to taste success on those marquee tours.

But other than Steven Smith and Nathan Lyon, key members of Australia's memorable triumph in 2014, no one else in their squad has won a series in South Africa and this looms as the last opportunity for several of them.

While the infamous events at Newlands from eight years ago will undoubtedly again be rehashed, Australia have too much going on to get bothered by all that.

After Matt Renshaw and the tail papered over cracks in the opener, Australia's long-held batting woes might have hit a nadir after a first innings capitulation in the second Test.

Changes have been demanded by an increasingly agitated Australian public, and there will at least be one with allrounder Cameron Green set to return from injury. But it remains unclear if there will be mass changes or whether selectors might give one final chance to the likes of No. 3 Marnus Labuschagne and allrounder Beau Webster. Steven Smith's ongoing neck problem also serves as a potential curveball.

Underlining the uncertainty, Australia will probably sport a new-look batting order for this match but it might look noticeably different by the home Test summer given several contenders have started the Sheffield Shield season well.

While Australia's travails have dominated the headlines ahead of the series-decider, South Africa have their own selection issues after quick Anrich Nortje was ruled out with a mild groin injury sustained during the second Test.

South Africa bounced back impressively after suffering their first defeat under Temba Bavuma's leadership. The return of spearhead Kagiso Rabada lit a fuse for a seam-heavy attack that roughed up and exposed Australia's fragilities.

A series victory would be particularly sweet for South Africa, whose triumph in 2018 was their first at home against nemesis Australia since readmission. It would give them significant momentum ahead of the second part of a blockbuster summer against England.

South Africa will rise to No.1 in the Test rankings with a victory that would continue the list of achievements under Bavuma and sit nicely with the WTC mace they currently hold.

For Australia, a draw would be enough to maintain their top-dog status but they will be hoping for much more in a bid to once again quieten the noise while also finding redemption in a port city that holds so much negative connotation for them.

South Africa WLWWW (last five completed matches, most recent first)
Australia LWWLW

Steven Smith returns to the scene of his career low point. This tour hasn't gone to plan for him so far. He endured a concussion scare during the first Test before a troublesome neck bothered him in the next match. Smith fell in tame fashion in the second innings in Gqeberha with an uncharacteristically wild pull against Rabada to midwicket. He has so far lost the battle with old foe Rabada, with Smith looking jarringly unsettled against fast-paced bowling. Smith, 37, is facing question marks over his Test cricket mortality although he's been able to silence doubters before. South Africa has been tough terrain for Smith, who averages 35.28 there compared to a career mark of 55.29. Apart from two Tests each in Bangladesh and the UAE, Smith averages more than 50 in all other countries. He'll be hoping to wind back the clock at least one more time in what would be a major tonic for Australia while also giving him a chance to finish on a high note in likely his last Test match in South Africa.

Reminiscent of Australia in the previous match, South Africa's batting order struggled before being rescued by a Bavuma masterpiece with strong support from the lower order. But the batting still feels shaky and will face a fired-up Australia attack that was left frustrated in the second Test. South Africa will look to opener Aiden Markram to set the tone and blunt the new ball. He has looked in sublime touch through the series, punctuated by an indefatigable 75 in the second innings at Kingsmead, but hasn't been able to go on with it. Markram will feel primed. Australia have brought the best out of him, having averaged 56.84, with three hundreds, from seven Tests. If he can further that record in Cape Town, then South Africa's chances of a series victory rises immensely.

Gerald Coetzee has been confirmed as Anrich Nortje's replacement in an otherwise unchanged South Africa side.

South Africa: 1 Aiden Markram, 2 Marques Ackerman, 3 David Bedingham, 4 Temba Bavuma (capt), 5 Matthew Breetzke, 6 Ryan Rickelton (wk), 7 Wiaan Mulder, 8 Marco Jansen, 9 Simon Harmer, 10 Gerald Coetzee, 11 Kagiso Rabada.

Cameron Green will return for Australia with Nic Maddinson dropping out and Matt Renshaw returning to opening. Beyond that, there remain a number of questions and Smith requires a fitness test on his back.

Australia (possible): 1 Travis Head, 2 Matt Renshaw, 3 Marnus Labuschagne, 4 Steven Smith, 5 Cameron Green, 6 Alex Carey (wk), 7 Beau Webster, 8 Pat Cummins (capt), 9 Mitchell Starc, 10 Nathan Lyon, 11 Josh Hazlewood.

There will be around 6mm of grass on the surface which is also on the drier side. Temba Bavuma said it could play similar to the second Test. In welcome news after the rain-affected second Test, mostly sunny weather is expected through the match with temperatures relatively mild.