Willem Alberts is in doubt for the Sharks in their crucial Super Rugby encounter against the Bulls on Friday, but Frans Steyn is expected to be ready for the clash at Kings Park.
Springbok forward Alberts suffered a knee injury during the second Test against England in Johannesburg last month and is one of several key players on the injury list ahead of the must-win match in Durban.
Bok back Patrick Lambie is also in doubt for the game, along with centre Paul Jordaan and lock Steven Sykes, who all face late fitness tests.
However, the Sharks are boosted by the availability of new signing Steyn, who announced his return to the coastal outfit prior to the June international break. He is expected to slot straight into the midfield alongside Tim Whitehead.
"Willem is very doubtful," coach John Plumtree said.
"Pat and Steven Sykes are also doubtful and we'll have to see where they are later in the week. Paul Jordaan tweaked a hamstring at training this morning and will have to undergo a fitness test tomorrow."
On the return of Steyn, who made 56 Super Rugby appearances for the Sharks prior to his two-and-a-half year stint at French club Racing Metro, Plumtree added: "We're lucky to have Frans back and Tim will go into the midfield with him.
"I'm excited about that combination. It's a new partnership, but hopefully they'll settle in quickly and complement each other's skills."
The Durban team, on a four-match winning run prior to the break -- before they were beaten by the Lions -- currently sit eighth on the table and have to win their last two matches to keep alive their play-off aspirations.
"We sort of had a gun to our head about five or six weeks ago when we got onto that winning streak and then let ourselves down against the Lions," said Plumtree.
"So clearly, when the gun is pointed between our eyes we react a bit better, I don't know why that is. So again it's a home game for us and we're hoping we can capitalise on that.
"There's plenty of character in the group and we'll have to dig deep again at the weekend to get on top of this Bulls team that's riding really high at the moment."
He believes they still have a good chance of making the top six, saying: "There's three of four teams on the same number of points and I guess it's just a case of controlling what we can control.
"There are still going to be a couple of twists, I don't think anyone would have expected the Hurricanes to beat the Crusaders in Christchurch. So there's still going to be a few surprises in the next couple of rounds."