Siya Kolisi has opted for surgery to treat the knee he injured playing for the Sharks against Munster in Durban last weekend.
Sharks Director of Rugby Neil Powell says his charges will need to be at their peak for the full 80 minutes against Leinster in the URC quarterfinals.
Leinster may be leading the charge for the URC title this season, but their road into both the European and URC finals is beset with pitfalls.
The Stormers and Western Province suffered a number of injuries in the two fixtures last Friday.
Bulls coach Jake White is feeling buoyed by his charges' new confidence as they head into their URC quarterfinal clash with the Stormers.
Kick-off times, dates and broadcast details for the United Rugby Championship Quarter-Finals have now been set for Friday, May 5 and Saturday, May 6.