Australia could be forced to make three changes for the second Test, with paceman Peter Siddle sweating on the results of scans on a sore back.
Siddle, who broke down with back stress fractures in February and only returned last month, pulled up sore after bowling on four consecutive days of the first Test.
Cricket Australia is expected to provide an update on the 31-year-old's fitness later on Tuesday.
Joe Mennie is poised to debut in the second Test, which starts on Saturday, if Siddle is unavailable.
Things started so well for the Aussies in Perth, but it quickly deteriorated as South Africa found its groove.
However, it is likely Jackson Bird or Chadd Sayers would also be summoned to Hobart as cover if the Victorian is injured.
Shaun Marsh (broken finger) will miss the second chapter of the three-Test series, while Adam Voges (hamstring) is also in doubt. Batsmen Joe Burns and Callum Ferguson have been drafted into the squad.
Questions were raised about whether Siddle was physically ready for the first Test, having only played three one-day games and a single first-class clash since a winter of rehabilitation.
The veteran right-armer was included in the Test side after bowling 26 overs during the preceding Sheffield Shield match.
Siddle delivered 38 overs at the WACA, where his pace dipped the longer the match dragged on.
"I probably haven't played as much as I would have liked but I felt good," Siddle said after day four of Australia's 177-run loss.
"It was a bit tiring to be out there but that's part of the game.
"When I'm feeling fully fit and have got some miles in the legs, that will all come together.
"It's just about finding some rhythm and that will get there."