Kagiso Rabada stood mid-pitch, hands on his knees, gazing at the turf. He was close enough to the ground to whisper to it, "how?"

How had the ball he had just delivered - full and swinging in - missed Tim Paine's pad and bat? How had Australia got to 162 for 5, all of 351 runs ahead? And how many more would they get?

By the close of play, the answer to the last question was known: Australia finished with a lead of 402, more than what South Africa may contemplate chasing, but the other mysteries remain.

How did a contest that was supposed to be so close meander into such a one-sided affair?

The short answer is that not for the first time, South Africa's batsmen have let their bowlers down. A first-innings of deficit of 189 requires something special in response, something as dramatic as the 47 all out of 2011, something that can be produced on a pitch that is doing more than this one, by bowlers who have a little more spark and a little more luck than these.

Take nothing away from the attack's persistence, which South Africans believe is ingrained into their DNA, because they kept at it, but they were frustrated by an Australian line-up that did the same. The visitors just kept coming, in that carefree and confident way they often do, and South Africa could not stop them.

Cameron Bancroft and David Warner scored at 4.3 runs an over, and seemed to face no menace against the new ball, against both pace and spin. A wicket had to come through a mistake and it did when Warner swiped one straight to mid-on. It was no surprise that Rabada took the opportunity to let off some steam. He gave Warner a send-off of sorts that the stump mics didn't pick up and the lip-readers say did not involve any expletives. He also cleverly passed his arm over his mouth as he said whatever he did, but it was unlikely to have been, "have a nice afternoon." And it didn't do anything to calm Rabada down.

The rest of his morning spell contained a lot of huffing and puffing - impressive movement, a beeline to off stump, pace and the short ball - but he could not blow the Australian house down. His annoyance grew, as did South Africa' desperation.

After lunch, their on-field conferences multiplied. Former captains AB de Villiers and Hashim Amla offered numerous pieces of advice to Faf du Plessis and the bowlers. They tried a few things, as much as they could, given the resources of a four-man attack, like close catchers that they thought could help Keshav Maharaj create pressure, and they did not succeed. Then, even technology deserted them.

Maharaj, a sensible and stoic cricketer almost all of the time, had Steven Smith playing for turn to an arm ball that flicked the front pad and wanted a review so badly, Faf du Plessis could not say no. Initially, it looked like a good call but the replays suggested umpire's call on impact. South Africa regarded it philosophically. "We have got faith in the technology but we were disappointed that we didn't get the right call," Malinbongwe Maketa, the assistant coach, said. "The technology is there and we back the technology. If it happens that you're on the wrong side, you have to suck it up". At least, they didn't lose the review.

Keshav Maharaj celebrates a breakthrough Getty Images

Five overs later, Rabada, who is usually more fired up than Maharaj, wanted a review against Shaun Marsh. He had sent a straight ball into Shaun Marsh's pads but it had pitched outside leg. A third review didn't go South Africa's way either, when Maharaj beat Shaun Marsh's inside edge with a ball that spun back into him but only returned one red on HawkEye and two on (impact and hitting) on umpire's call, which was not out. By then, Dean Elgar had dismissed Smith and Rabada had changed ends and got rid of Mitchell Marsh, but Australia were 345 runs ahead.

Two overs later, Paine just missed the Rabada delivery that did everything right except make contact. And South Africa's position became clear: they have been outgunned. Maybe because they were undercooked - only three of the top six had played competitive cricket in the last few weeks - maybe because they underestimated the challenge they would face or maybe because there are underlying issues. And it's those that need examining.

South Africa's players have more on their minds than just this match, or even this series. Behind the scenes, Cricket South Africa is gearing up to redraft their Memorandum of Understanding with the South African Cricketers' Association and have already floated the possibility of relooking at the revenue sharing model. One person closely connected to the discussions has told EPSNcricinfo they expect it to be the "biggest fight," CSA and SACA have had in their 14-year acquaintance.

The uncertainty does not stop there. The fate of the Global T20 League, which for many players is a deal-breaker in determining whether they continue their careers in South Africa or choose to look for greener pastures overseas, is still up in the air. Whether or not the players knew that both issues were being discussed, first by a meeting between member CEOs and presidents and CSA executive committee members and then at a board meeting, at a luxury golf estate 40 kilometres north of Kingsmead, doesn't matter. They are issues bubbling and boiling in the background and maybe this is the series in which they are starting to spill over onto the field. Player unhappiness in administration often leads to underperformance. CSA's suits should take note.

Just as South Africa may have been wondering what else could go wrong, their opening batsman Dean Elgar dislocated a finger while taking the catch to dismiss Mitchell Starc. AB de Villiers dropped a chance he would have taken on any other day. Nathan Lyon reached for a Rabada delivery and guided it upwards of second slip. De Villiers jumped and got both hands to it but could not hold on.

Rabada, expressionless, arms dangling by his side, just walked back to his mark. "How?"