The Springboks are concerned about injuries to their vice captain Victor Matfield and centre Jean de Villiers after only just surviving their opening World Cup game against Wales in Wellington.
Matfield and de Villiers both limped off during the match, which the Springboks won 17-16, and while coach Peter de Villiers wasn't specific about their injuries, he's very worried about them and he's awaiting the findings of full medical checks on both players.
Another lock Bakkies Botha wasn't selected for yesterday's match because of an achilles injury which is an on-going concern.
Meanwhile Argentina's centre Gonzalo Tiesi and Japan number eight Ryukoliniasi Holani have both been ruled out of the tournament with knee injuries.