Springboks face fresh injury hurdle with Kolisi, Arendse and Pieter-Steph ruled out

The Springbok captain is set for a four-week spell on the sidelines after sustaining a knee injury, putting his involvement in the back-to-back Rugby Championship clashes in New Zealand next month in serious doubt.

It's the second setback Kolisi has suffered this international season after missing both of the Italy Tests with a stiff neck.

To make matters worse for the Boks, Pieter-Steph du Toit will also miss the Cape Town Test match after sustaining a concussion. Erasmus said that Du Toit will miss the round two fixture but should be back in the selection frame for the two Tests in New Zealand.

Meanwhile, both wingers - Kurt-Lee Arendse and Edwill van der Merwe - also picked up injuries against the Aussies and are sidelined for the next three weeks.

"Siya is out, I think for four weeks," Erasmus revealed.

"Pieter-Steph is out for a concussion, Kurt-Lee with a knee, and Edwill injured his ankle."

Thankfully, the Boks do have the depth to deal with these absences in most positions. Cheslin Kolbe is set to return to action for the Boks this weekend, while Makazole Mapimpi is also available to fill in on the wing.

The back-row is a bit more of a problem as the Boks are already dealing with the unavailability of several No 8s, including Cameron Hanekom, Jasper Wiese, Elrigh Louw and Juarno Augustus. Kolisi was shifted to the position precisely because of this.

Evan Roos was put on stand-by for the Rugby Championship and could be drafted into the squad, while Cobus Wiese started in the number eight jersey against Georgia in Nelspruit and may be asked to do the same against Australia this week. Jean-Luc du Preez and Kwagga Smith could also fill Kolisi and Du Toit's voids.

Meanwhile, Bulls lock Ruan Nortje featured at blindside flanker for his club this season and may well offer the best replacement for Du Toit, offering a similar work-rate and lineout ability as the double World Cup winner.

The Wallabies' memorable win also came at a price, with winger Dylan Pietsch and veteran prop James Slipper both ruled out of the Cape Town rematch. Pietsch, who sparked Australia's comeback with a first-half try, suffered a broken jaw in a collision with Siya Kolisi, while Slipper failed his HIA after reporting concussion symptoms.

Both players have returned home, where they are joined on the sidelines by Ben Donaldson, who missed the Johannesburg clash due to an abductor strain. To bolster their squad, coach Joe Schmidt has called up Filipo Daugunu, Rhys van Nek and Hamish Stewart for the second Test.

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