South Africa-based stars of the 2019 Rugby World Cup-winning Springbok squad were told Friday that they can start contact training after being unable to play since March because of the coronavirus.
However, whether the champions will be able to defend the Rugby Championship title this November and December remains uncertain.
Franchise coaches say players need at least four weeks of contact work before they can play, meaning a local competition cannot start before the weekend of September 25-26.
Were the Springboks to compete in the November 7-December 12 Championship, which New Zealand is likely to host, they would have to leave South Africa by October 18.
Assuming that domestic matches are staged each weekend in South Africa, potential Springboks would have played only four games by the travel deadline.
Referring to the Championship recently, Springboks coach Jacques Nienaber said that "unless we can play six domestic matches, I do not think we will go (to New Zealand)."
SA Rugby chief executive Jurie Roux said: "Ultimately it will be a rugby decision, so I will lean heavily on our director of rugby (Rassie Erasmus) and the Springbok coach.
"They will decide where we stand and whether we have enough time to be properly prepared for international matches against New Zealand and Australia."
Ordinarily, the Rugby Championship is a six-round competition staged between August and October and involving Argentina, Australia, New Zealand and South Africa.
Each team plays the other three at home and away with the one accumulating the most points from wins, draws and bonus points being crowned champions.
- Format scrapped -
Covid-19 meant that format had to be scrapped and New Zealand were tipped to host all six rounds as they have been less affected by the pandemic than the other three nations.
Announcing the move to contact training after five weeks of non-contact practice, Roux said "we are moving in the right direction and urge the rugby 'family' to bear with us".
He did not, however, disclose details of the domestic competition behind closed doors that would see rugby played in South Africa for the first time since March 14.
Originally, two options were reportedly being considered: a two-round competition between the four Super Rugby sides from South Africa followed by a single-round Currie Cup.
The former proposal appears to have been dropped with a double-round Currie Cup the likeliest way forward.
It would involve Super Rugby teams the Bulls, Lions, Sharks and Stormers, plus the Cheetahs, Griquas and Pumas.
The Kings would also have been invited, but the cash-strapped team announced this week that they would not play again this year to avoid further debt.
South Africa will be the last major rugby nation to restart domestic competition with New Zealand playing from mid-June and Australia starting in early July.
The English Premiership and Pro14, involving Irish, Italian, Scottish and Welsh sides, have begun and the French Top 14 is set to kick off over the first weekend of September.