Australia’s growing casualty count is boosting South African confidence, despite the home side holding the whip hand in the Boxing Day Test.
The tourists trail by 197 runs after day two at the MCG, and their last seven Test innings have all finished below 200.
But the in-form Australian bowling attack could be down one or two key members for South Africa’s second visit to the crease.
Mitchell Starc is managing a finger injury he suffered on day one and is understood to be no certainty for next week’s third Test in Sydney.
All-rounder Cameron Green, who took his first five-wicket Test haul on Monday to rout South Africa, is also in doubt with a finger injury.
The index finger on Green’s right bowling hand was bloody and swollen on Tuesday after a delivery from paceman Anrich Nortje jammed it against the bat handle.
Green was forced to retire hurt and went to hospital for scans.
“That’s going to be a big factor,” Nortje said of the Australian injuries.
“It’s going to be crucial to bat for as long as we can.
“The more overs the bowlers are to bowl, the more maybe a backup bowler … would have to apply themselves.
“That’s going to be a crucial stage for us … work through the difficult stages with our top order and then try and cash in a little bit later.”
Nevertheless, Australia will resume on Wednesday full of confidence at 3-386 as they close in on their first home Test series win over South Africa in 17 years.
Rain is forecast for Wednesday after Tuesday’s oven-like temperatures, when several players, including Nortje, suffered with cramp.
Nortje hit by Spidercam in on-field accident
Nortje was also another bowler to be injured at the Boxing Day Test, in highly unusual fashion.
The wire-guided Spidercam, which hovers above the players, went too low and collected the paceman from behind as he was fielding.
He is being monitored for soreness in his left shoulder and elbow, which took the impact as Nortje was knocked to the ground on day two of the Test.
The camera hit Nortje at some pace, but he was on his feet immediately and was able to keep bowling.
While Nortje had to leave the field later, it was because of cramp as the players roasted in the mid-30s conditions.
Spidercam was not used for the rest of the day and its operators spoke to the South Africans, with the incident blamed on human error.
It is understood the equipment will be back in use on Wednesday.
“I didn’t know what hit me. The one thing we’ve spoken about earlier is how low it is,” Nortje said.
“I don’t think it should be travelling head-height.”
After starring with 200 in his 100th Test, Australia opener David Warner had to retire because he was so affected by the conditions.
The misfiring South African top order baked in the field on Tuesday ahead of an attempt to rally in their second innings.
A year ago, Victorian fast bowler Scott Boland exploited home-ground conditions brilliantly on his Test debut to rout England in the second innings of the MCG Ashes meeting, taking six wickets.
If Starc and Green are out of action, Boland and captain Pat Cummins will shoulder the bowling burden along with off-spinner Nathan Lyon.
AAP