Crusaders wing Johnny McNicholl could be out of action for four to five months after suffering a broken ankle against the Stormers.
The talented outside back will take no further part in this season's Super Rugby tournament after he fractured a fibula bone in his left leg was forced off the field in Saturday's 19-14 victory in Cape Town.
The seven-time champions will also be without All Blacks front-rower Owen Franks for this weekend's clash with the Sharks. The tighthead prop was forced to leave the field with a rib injury.
Telusa Veainu will join the squad as cover, while specialist tighthead Nepo Laulala is likely to replace Franks in the Crusaders starting line-up.
Full-back Israel Dagg is hopeful of playing against the Sharks this weekend, after missing the game with tight hamstrings.