All good things come to an end and Temba Bavuma's unbeaten run as Test captain now has. It was unlucky No. 13 for the South Africa skipper, whose streak had stretched back to his appointment in February 2023 and includes a World Test Championship final success and a series win in India. Now, he knows what the opposite feels like. It's fair to say he doesn't like it.

"It is disappointing. It's not the way you want to start a series, any kind of series, let alone just against a top outfit like Australia," Bavuma said after defeat in Durban. "The emotions are obviously still a little bit high. You probably want that to settle before you get into the conversations but there are obvious things that we could definitely improve on. No one is happy in that change-room, looking at the result that has played out."

Despite his heightened feelings, Bavuma's thoughts were clear and critical as he assessed his team's performance, which he broadly described as under-par.

South Africa were only in the contest on the first day, when they had Australia 124 for 6 before Matt Renshaw formed partnerships with Pat Cummins and Nathan Lyon which proved match-winning. Bavuma acknowledged that the longer Renshaw stayed with the lower order, the more despondent South Africa became. "Any other day, as a bowling attack, you're backing yourself to restrict them to less than 250 and for them to go and get that [390], mentally that took a little bit out of us," he said.

At that point, Bavuma's own tactics were under scrutiny. His fields were set so that Renshaw could comfortably keep strike. At one point, Renshaw faced the first ball of 13 consecutive overs and milked the double-spin attack at will. Bavuma pinned it more on Renshaw and Cummins getting the best of the batting conditions than any major strategic flaws, but South Africa's lack of bite could not be ignored.

"When Renshaw and Cummins came together, conditions were a lot more in their favour and they became a lot more ruthless. They didn't give us anything. They occupied time at the crease, the wicket flattened out and the ball got softer. The momentum that they gathered in that partnership, they just ran with it. Renshaw absorbed pressure, put us under pressure when he saw the opportunity and the way he countered the threat of the spin, made things difficult for us in terms of holding pressure on the other side. We've seen a lot of innings and that's probably one of the better ones."

Sapped from 137.2 overs in the field and from ceding the advantage, South Africa were then not able to cash in on a surface that remained good for run-scoring well into the fourth day. "The conditions were good to bat and we were not able to make the most of it," Bavuma said. "Our lower order hung in, they spent time at the crease and really showed what was possible once that ball got soft. In our second innings, we made a good effort, especially from a guy like Aiden [Markram, who made 75], but just wasn't enough fight and mental aptitude from us to get us into that last session."

South Africa's 284 was their fourth-highest Test total without a single batter crossing fifty, which is the strongest indication of the inability to convert their starts and the match felt lost in that innings. When they went 84 for 1 to 99 for 4 on the third day, with a middle order of Tristan Stubbs and Wiaan Mulder, South Africa seemed, and ultimately were, too far behind.

The quality of Australia's attack, who provided what Bavuma called "real execution of top level skill ... there's no one where you feel like you can take a breather", cannot be discounted but the manner in which South Africa were dismissed suggests there is more to it than just excellent bowling. In the first innings, all South Africa's batters were caught in the field and pretty much all of them were guilty of poor shot selection.

Bavuma owned up to several "soft dismissals", including his own. He was out to an offspinner twice in the game for a total of four runs "so maybe there's something that I need to have a look at there".

Like most of his team-mates, Bavuma has had limited red-ball match time ahead of this series with only two rounds of domestic first-class cricket played in the lead up to this early season series. Did lack of game time play a role? "I can never sit here and use that as an excuse," Bavuma said. "I think we knew that that was going to be in front of us. We had the opportunity to prepare as much as we could. But you can never really prepare for Test cricket without playing Test cricket. A lot of the mistakes we made out there were mental so that's where we really let ourselves down. Whatever cobwebs were there, I guess that will be dusted off."

Exactly what caused the mental fragility in South Africa's line-up will have to be studied in the days to come but they remain steadfast that it was not a case of assuming the best form of defence was to attack. After day three, batting coach Ashwell Prince said he didn't think South Africa were "too aggressive" and Bavuma stuck to that line.

"If the wicket says play a certain way, we try to play a certain way. That's been the plan that we've followed that has brought us some level of success," he said. "I definitely don't think guys were throwing caution to the wind, playing recklessly or anything like that. I think it's a certain level of pressure that maybe some of the guys weren't really accustomed to, you know. But the first game's out the way. In Gqeberha, we should be better prepared."

The series is now set up similarly to the way it was eight years ago, when South Africa were beaten by Australia in Durban but went on to win in Gqeberha, Cape Town and Johannesburg and there's no doubt they'll look back on how they did that. "You look for motivation in all places, right?" Bavuma said. "That's one place."

Markram was a key protagonist then too. In defeat at Kingsmead in 2018, he again showed stubborn resistance. The difference was that then, he had Quinton de Kock for company in 147-run sixth-wicket stand. This time, in the same position was Kyle Verreynne, who was among the worst offenders in the line-up. Whether the axe falls on him will be one of the biggest talking points over the next four days but all indications are that some change is necessary.

"The guys that you saw who took the field are guys that we have full confidence in," Bavuma said. "Going forward, there's going to be conversations that need to happen. Guys understand that's just how professional, high-level sport goes. If you're not delivering the goods and if there is someone else who's waiting in the wings, they'll get that opportunity."

Bavuma, too, is now fundamentally changed. While he has experienced defeat as a player, he has now experienced it as a leader and will need to consider that alongside his batting in his debrief. He already started shortly after the game, when he took a moment to himself, before addressing the media. "It was just reflecting on the game," he said. "Sometimes you sit there in the changing room and you can get caught up with everything that is happening. For me, it was just to try and clarify whatever thoughts that I had in my mind in terms of how the five days went by, looking at the way they went about their business in areas that we can improve on, and then having a little futuristic look at potentially Gqeberha and how we can shape up there."

All good things come to an end, that's true, but nothing lasts forever either. South Africa will remember that as they convince themselves to move on quickly.