CJ Van der Linde called up by Springboks
The South African Rugby Union says Van der Linde will have further assessment on a groin injury before he is cleared to tour while Sharks second rower Mostert has been called up as cover for Johann Muller, who has a hamstring injury.
The Springboks are already missing 21 injured players for their away leg of the Tri-Nations and will decide if Van der Linde and Mostert remain with the squad later this week.
Coach Peter de Villiers said: "We've been hard hit by injury in several positions. We're preparing for all eventualities."