Head coach Andrew McDonald conceded Australia's batting weaknesses had been exposed on the fourth day in Gqeberha but he would not "hang anyone out to dry" after they collapsed for 99 and were forced to follow-on for just the third time since 1988.

After reaching 100 for 1 in the second innings, Australia closed on 156 for 4, still 170 away from making South Africa bat again with Marnus Labuschagne's dismissal, lofting to mid-on, sparking a late-afternoon surge from the home side. Travis Head was unbeaten on 87 and McDonald confirmed that Steven Smith would be able to take part on the final day despite suffering a neck problem that meant he slipped down the order.

The state of the game was a remarkable turnaround from just 48 hours earlier when South Africa finished the second day on 97 for 5. They were able to transform that into 425 before Marco Jansen led the way with the ball, taking 5 for 33, while Kagiso Rabada has made an impact on his return and Simon Harmer played a key role in the second innings to help absorb the loss of Anrich Nortje to injury.

"I think any time when anything unfolds at that speed it takes a couple of players communicate and navigate through that and we weren't able to get any partnerships," McDonald said of the 99 all out. "We've had some of these moments across the journey, so we're not a perfect batting unit and I've never said that we are.

"The speed at which that happened and the momentum that South Africa were able to gain through that, we didn't envisage coming here and looking at a follow-on that, that's for sure. We felt like we were good enough on that surface, it didn't play too many tricks, either. There was a bit of bounce. You do have to give a little bit of credit to the South African attack as well, the way they exposed some of our deficiencies in that, so I don't want to take anything away from that.

"But there was some batter error there and I think we are better than that but, as it sits right now, I can't defend that."

Australia took the first Test in Durban handsomely by 214 runs. Despite question marks over the batting for a few years they have not lost a Test series since the away trip to India in 2023 and McDonald defending their long-term record. However, frailty was on display when they lost the World Test Championship final to South Africa last year and in the more recent defeat against Bangladesh in Darwin.

"It's only a week ago that we were a really, really good team," McDonald said. "We're sitting here right now and we're starting to defend a team that's performed exceptionally well. You'll be looking for a grab and talk about the negatives and what should happen and what should move. This team's been a really consistent team over a long period of time so I'm not going to sit here and hang anyone out to dry."

"It's disappointing, but as I said, those players that sit in that room are still the same players that performed exceptionally well last week. I have great belief and trust that the skillsets in that room, in particular tomorrow, can go out there and potentially turn this one around.

"If that doesn't unfold, then we move into Cape Town, we reload and we go again. A great strength of this group is on significant setbacks, and I'd say this is a significant setback in terms of the way that we play, we've been able to respond."

McDonald refused to be drawn on potential changes for the final Test while this game was still ongoing, which is standard practice, but when asked separately about Cameron Green's recovery indicated he would be available for selection. Green has not played since suffering an abdominal strain in the final ODI in late September and is unlikely to be available to bowl but would warrant a place as a specialist batter.

Josh Inglis and Cooper Connolly are the other batting options from the original squad while the uncapped Sam Harper currently remains on the tour having been called up after Inglis was ruled out of the opening Test with a fractured finger.