Sharks prop Toby Rudolf will miss 6-8 weeks after suffering a syndesmosis injury in last weekend's win against the Knights.
Rudolf damaged his left ankle in the second half of the match at McDonald Jones Stadium. He didn't return after leaving the field in the 55th minute.
It's a frustrating setback for one of the game's most popular players, who sat out the first three rounds this year following off-season shoulder surgery.
Meanwhile, centre Kayal Iro has recovered well from a hamstring tear and is expected to be available in the coming weeks. Iro hasn't played since Round 4.
Front-rower Braden Hamlin-Uele is on the cusp of returning from a knee cartilage injury having been named on the extended bench for Sunday's clash with the Tigers.
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