Cricket South Africa confirmed that Rabada is undergoing rehabilitation for a right hamstring injury and will miss the three-match ODI series against Australia from September 24 to 30. His availability for the Tests will be assessed closer to the series.
However, reports have suggested the injury is a grade-three tear that could keep the 31-year-old sidelined for nine or 10 weeks. If that recovery timeline is accurate, Rabada would miss at least the first Test in Durban on October 9 and potentially the entire series.
Rabada's absence would be a significant setback for the Proteas. He has taken 340 wickets in 73 Tests at an average of 22.03 and was instrumental in their World Test Championship triumph over Australia last year, claiming nine wickets in the final at Lord's.
He also has an impressive record against Australia, with 58 wickets at 21.39 from 11 Tests.
South Africa nevertheless have considerable pace depth to call upon. Lungi Ngidi, Marco Jansen and Corbin Bosch are likely to shoulder much of the responsibility, while Gerald Coetzee, Kwena Maphaka and Dane Paterson are among the other options.
Anrich Nortje could also come into consideration despite not playing Test cricket since 2023, while Gerald Coetzee has recently impressed for South Africa A against Bangladesh A.
The Proteas' need for Rabada is heightened by the importance of the upcoming home season. They face Australia, England and Bangladesh before travelling to Sri Lanka, with seven wins from their next 10 Tests required to guarantee another World Test Championship final appearance.
Rabada's return date therefore remains a major question as South Africa prepare for a demanding campaign.