Bulls centre Wynand Olivier is likely to miss his team's Super Rugby clash against the Waratahs on Friday after injuring his ribs playing against the Rebels.
The Bulls have revealed that Francois Venter or Johan Sadie is likely to replace Olivier for the Sydney clash.
Meanwhile Prop Rayno Gerber and loose forward Gerrit-Jan van Velze has been called into the Bulls touring squad in Australia.
They will replace Frik Kirsten and Jacques Potgieter, who sustained tour-ending injuries in the Bulls 41-35 win over the Rebels in Melbourne on Friday.
Kirsten broke his hand and will be out for six weeks, while an injured knee will keep Potgieter out for between six and eight weeks.
They will return to South Africa on Monday.