The Australians will head to the African nation for a series of one-dayers - one against Ireland on September 27 and five against the Proteas, beginning September 30.

The Proteas could have used this series to try and prepare to handle Starc and Hazlewood on their reciprocal trip to Australia, with the three-Test series beginning in Perth in the first week of November. But that now won't be possible, with Starc to rest after completing the full tour of Sri Lanka, and Hazlewood due to arrive home on Friday, missing the final one-day clash in Pallekele on Sunday, and the subsequent two Twenty20 games.

Starc has been the tourists' stand-out performer in Sri Lanka, claiming 24 wickets in the Test series - a record by a visiting quick in a three-Test series there. He also has nine wickets through the opening four one-day internationals.

Hazlewood had a largely disappointing tour, and the selectors will have to debate whether he has the right skills to flourish on the sub-continent, with the tour of India from February in mind.

Cricket Australia selection chairman Rod Marsh said the time was right to rest Starc and Hazlewood, ahead of a busy summer campaign.

"Both Mitchell and Josh have had big tours of Sri Lanka and have a heavy workload ahead of them with 10 Tests to be played this summer," Marsh said.

"As such, it is important they are managed appropriately and we believe missing the tour of South Africa is the right time for them to take a break.

"This also provides a good opportunity for some of our up-and-coming fast-bowler to push for selection.

"With a number of bowlers currently coming back from injury it is important for us to continue to build up a battery of quality fast bowlers for Australia."

The squad for the South African tour will be named within days.

Hazlewood joins skipper Steve Smith in having left Sri Lanka while the one-day series was on. But, in Hazlewood's case, his absence comes with the tourists enjoying an unbeatable 3-1 lead. Starc is likely to be rested from the dead rubber, leaving quicks Scott Boland, John Hastings and James Faulkner and spinners Nathan Lyon and Adam Zampa to carry the attack.

Smith controversially was rested and sent home after the opening two matches. Allrounder Mitch Marsh returned home on the eve of the series, having initially been named, while his older brother, Shaun, was sent home after breaking his finger in game three.

The decision to rest Hazlewood and Starc comes at a time when Australia cannot afford to have more injuries to their fast bowlers, for Pat Cummins has only just resumed bowling, James Pattinson and Peter Siddle are still on the mend and Nathan Coulter-Nile is out indefinitely because of a back stress fracture.

The Australians have a hectic summer ahead, for the Proteas' tour will be followed by three Tests against Pakistan. There are also a plethora of one-day internationals, including a short tour of New Zealand, before four demanding Tests in India where the tourists will be desperate to end a nine-game losing streak on the sub-continent.

Ryan Harris, the former Australian quick, will be an assistant bowling coach to David Saker in South Africa. This will be Saker's first series in charge of the bowlers, having replaced South African great Allan Donald, who had held the role on a caretaker basis through Sri Lanka. Harris is currently the assistant coach of the national performance squad.