Even throughout the first day, the game swung wildly. One moment, we were eyeing off the highest visiting scores at the ground, and Lindsay Hasset's 167 was looking slim. The next, a whole Australian team was struggling to pass it.
Australia began its work on a lively pitch, defended 13 overs for 18 sensible runs, ransacked the next 13 overs for 80, then lost 10 wickets for a further 145.
David Warner threatened to wreak destruction with the bat, before Kagiso Rabada and Lungi Ngidi made good on their promise with the ball.
The end result was 243 all out for Australia, before South Africa reached 1-39 at stumps.
Should South Africa make good its advantage, it will be another episode in what these teams do. In 2011, the series crashed one way in Cape Town, slewed the other at the Wanderers, then left spectators dry when they were thirsting for a decider.
In 2014, the third match was reintroduced, and became a classic in its own right, decided by some Ryan Harris brilliance with a couple of overs to go.
Whatever the hypotheses as to why, these series produce great contests. The two teams are like dust: You can sweep them away in one moment, but they will rise up after you are done.
With live grass on the wicket, clouds overhead, and rain about, South Africa captain Faf du Plessis was glad to lose the toss. Steve Smith went the Australian Route 1 and chose to bat.
The reasoning is that you can battle through a tough first period, then prosper. This Test saw it happen in fast forward. Vernon Philander seamed the ball a mile, Rabada operated at pace, but Warner and Cameron Bancroft bunkered down for the first hour.
Then in four overs after the drinks break, they smashed 44 runs, and South Africa had no answers.
Warner drove two boundaries through cover, so third slip moved to fill the gap. Next ball he edged through third slip, so back the catcher came. Back went Warner, driving a brace and then another four through cover. All this in one Rabada over.
It seemed a catharsis for Warner, after the scrutiny he has endured for the past few days. His batting was as crisp as ever. One second it looked like he was digging out a yorker, the next that ball was speeding down the ground for four. His half-century brought an understated celebration.
If the openers' job was to negotiate the first session, they made it - just. Philander finally got rewarded on the stroke of lunch, drawing Bancroft's edge to end the batsman's stay for 38, and the partnership at 98.
It was a mighty platform. But where South Africa had bowled well and without luck in the first session, there would not be many near-misses in the second.
Shortly after his sandwiches, Philander doubled down with the faintest nick from Usman Khawaja for 4, continuing the number three's struggles away from home.
Proteas rewarded for showing faith in Ngidi
Then it was Lungi Ngidi with the key breakthrough, a fast delivery that jagged back off the seam and smacked the bails above middle stump after cutting Warner in half.
Walking off for 63, Warner was left watching the big screen to divine just how that ball had gone so comprehensively through him. The vision did not leave him much closer to an answer.
That Ngidi was even playing was down to an impressive choice by South African selectors. Morne Morkel had been ineffective in Durban, and the other three bowlers had struggled to maintain pressure without a fourth backing them up.
With Morkel retiring at the end of the series, the easiest option would have been to bow to sentiment and back him. But selectors made the tough call, and Ngidi lent their quartet a more menacing aspect.
Steve Smith and Shaun Marsh steadied, adding 44 runs, but when the ball started to reverse, Rabada brought calamity.
It started with Smith stuck on the crease as a ball jagged into his pads to beat his stroke across the line.
Tim Paine was promoted to reprieve Mitchell Marsh, who had come down with gastro, but that only bought the all-rounder eight deliveries, as Rabada's next over removed Shaun Marsh leg before.
Never mind. In and out may have been the story of Mitchell Marsh's day, and it was the same for his innings. An inside edge, and Rabada had collected the set of brothers within three balls.
That brought the tea break, with one ball left in the over. Rabada used it to good effect after the interval, nicking off Pat Cummins to extend his own streak to four dismissals in seven deliveries.
He did not get the hat-trick, but two overs later he huffed and puffed and blew down Mitchell Starc's house to complete a five-wicket haul within a single spell.
The significant downside was that television footage emerged showing him bumping shoulders with Smith after the latter's dismissal. With a poor disciplinary record, that sort of contact could see Rabada tipped over the points threshold for a two-match suspension. Stay tuned.
At 8 for 182, South Africa should have polished Australia off. But the bowling tried too hard, as it often does to the tail, and some important late resistance between Paine, Nathan Lyon, and Josh Hazlewood whacked and blocked 61 more runs.
How important those might be in the final analysis. The eventual 243 may not be that far below a decent score.
In a dozen attempts here, only once has Australia made over 300 – and that takes us back to 1950 again, when Hassett's innings combined with tons from Neil Harvey and Arthur Morris.
But the South Africans know this ground, and it will take more bowling brilliance from Australia to hold off the likelihood of a 1-1 series score. Between these sides, nothing could be more appropriate.