Injured Springboks captain Kolisi out for four weeks

South Africa captain and flanker Siya Kolisi will be sidelined for four weeks due to a knee injury suffered in a shock loss to Australia at the weekend, coach Rassie Erasmus said on Monday.

The injury occurred early in the second half of a 38-22 defeat in Johannesburg last Saturday in a Rugby Championship first round match.

Kolisi will not only miss another Test against the Wallabies, on Saturday in Cape Town, but is also likely to be sidelined for the Springboks' two away matches against arch-rivals New Zealand next month.

Erasmus said three other starters in Johannesburg -- wings Edwill van der Merwe (ankle) and Kurt-Lee Arendse (knee) and flanker Pieter-Steph du Toit (concussion) -- will also miss the Cape Town Test.

In the absence of Kolisi, outside centre Jesse Kriel will take over as captain of a team that slipped from first to third behind New Zealand and Ireland in the world rankings after the shock defeat.

South Africa built a 22-point lead within 18 minutes, then failed to score again while Australia crossed the tryline six times for a first victory in Johannesburg since 1963.

"Obviously, everyone is ashamed, no one is proud of themselves," Erasmus told a press conference in Cape Town.

"It only strengthens our cohesion and our desire to do well. You do not learn anything from a match like that -- when you see what we sometimes handed them on a plate."

Australia have also been hit by injuries with wing Dylan Pietsch (broken jaw) and prop James Slipper (concussion) flying home after the Ellis Park Test.

Coach Joe Schmidt has called up three replacements, wing-centre Filipo Daugunu, centre Hamish Stewart and prop Rhys van Nek, as cover.

The Wallabies hope captain and No 8 Harry Wilson, who scored two tries in Johannesburg before limping off injured, will be fit for Cape Town.