Australia won the toss and chose to bat first in SCG Test.
The 26-year-old returned a positive rapid antigen test after feeling unwell before the start of the play. Renshaw, who returned to Test cricket after a nearly five-year absence, was named in the playing XI and was listed to bat at number six.
As per Cricket Australia, the team management confirmed that Renshaw will "continue to take part in the match" despite testing positive for Covid-19. But the batter was separated from the rest of the squad and was seen sitting away from other players in the dugout during the morning session.
During the Commonwealth Games 2022, Australia all-rounder Tahlia McGrath was allowed to play the final against India despite being returning positive for Covid-19 before the toss.
Even during the T20 World Cup 2022, Matthew Wade was set to play against England in the group 12s stage match despite testing Covid positive.
"I still don't know how we have not had Covid in our team now I think about it. It feels like it is back to normal life. Even on Christmas, we were able to have more families there than we have in the past. Interstate travel, the Sydney guys are staying at home – life feels really normal.
Everyone is in great spirits because everyone feels like they have got their summers back to normality. It is great. I think you have seen it with crowds as well, they have been fantastic this summer,” Australia Test captain Pat Cummins said before Renshaw tested positive.
Pat Cummins won the toss and chose that Australia will bat first.
Australia playing XI:
David Warner, Usman Khawaja, Marnus Labuschagne, Steven Smith, Travis Head, Matthew Renshaw Alex Carey (wk), Ashton Agar, Pat Cummins, Nathan Lyon, Josh Hazlewood
South Africa playing XI:
Dean Elgar (capt) Sarel Erwee, Heinrich Klaasen, Temba Bavuma, Khaya Zondo, Kyle Verreynne, Marco Jansen, Keshav Maharaj, Simon Harmer, Kagiso Rabada, Anrich Nortje
(Cricket Australia inputs)