Steve Smith top-scored for Australia in the first innings of the second Test in Gqeberha with 28 runs, a knock that saw him surpass the 11,000-run milestone in Test cricket. During his innings, a delivery from Kagiso Rabada caused the right-hander's neck to jolt backwards, leaving him visibly uncomfortable as he continued batting.

Smith did not take the field when Australia began their second innings, with a sore neck keeping him out of the start of the batting order. The injury prompted the medical team to work extensively on the veteran batter, and he was observed wearing protective padding around his neck in the change room during Australia's second innings.

Australian head coach Andrew McDonald addressed Smith's fitness ahead of Day 5, expressing optimism about the star batter's availability.

"We have seen the physio working on him, so he will bat tomorrow. It is not something that will rule him out of the innings, but it was just a little bit more time than we expected on the back of the first innings. Sometimes he changes his technique when he is fully fit too, but he was limited in what he could do," McDonald was quoted as saying by the ICC.

Australia's position and Smith's role in the comeback

Australia faced a challenging position at the close of Day 4, with the team reduced to 156 for 4, still 170 runs short of forcing South Africa to bat again. The tourists had been forced to follow on after being skittled for 99 in their first innings in reply to South Africa's 425 for 9 declared.

McDonald acknowledged the difficult circumstances but backed the batting unit to respond. He explained that the decision to rest Smith was made to allow the team to navigate through to the final day, hoping the batter would be in better condition to contribute when he returned to the crease.

"We felt it was best to hopefully get the batting unit through to tomorrow and then hopefully he is better placed," McDonald said.

The Australian coach expressed confidence in the squad's ability to mount a comeback despite the first-innings setback.

"I have great belief and trust in the skill sets in that room, and in particular tomorrow, we will go out there and potentially turn this one around. If that does not unfold, we will go to Cape Town, and we will reload. We will go again. A great strength of this group is on significant setbacks - and I will say this is a significant setback - we have been able to respond," McDonald said.

Travis Head remained unbeaten on 87, and nightwatchman Scott Boland on 2 not out overnight and Australia will look to build a partnership on Day 5. Smith's return to the crease would provide a significant boost to the team's hopes of salvaging a draw in the rain-affected match.