Springbok captain Jean de Villiers is in doubt for next month's World Cup after suffering an injury in their Rugby Championship loss to Argentina in Durban.
De Villiers fractured his jaw, which will rule him out for up to six weeks.
The 34-year-old has only just returned to the game after spending eight months on the sidelines after suffering a serious knee injury against Wales in November.
With 107 Test caps to his name, de Villiers is expected to retire from international duty after the World Cup.
De Villiers, Marcell Coetzee and Willie le Roux will all miss next weekend's rematch with Argentina in Buenos Aires.
Coetzee suffered a medial collateral ligament injury to his left knee which will rule him out for approximately six weeks.
The injury is unrelated to the knee injury he suffered a few weeks ago in Brisbane.
Le Roux sprained his ankle early in the match against Argentina and will also not be considered for the trip to Buenos Aires.
He will undergo scans early in the week to determine the exact nature of the injury.
Several players on the way back from injury such as Victor Matfield, Fourie du Preez and JP Pietersen, will be assessed before a decision on their availability for next weekend will be taken.
Although Steven Kitshoff, Frans Malherbe, Willem Alberts, Warren Whiteley and Jan Serfontein were declared fit to play last week, Springbok coach Heyneke Meyer decided to give them an additional week to recover and they will be considered for selection next week.
Apart from De Villiers, Coetzee and Le Roux, other injured players who will not be considered for the trip to Buenos Aires, are Jannie du Plessis, Coenie Oosthuizen, Francois Louw and Duane Vermeulen.
Winger Juan Imhoff scored a hat-trick of tries as Argentina recorded a stunning first win over South Africa in Durban.