Central Coast are at risk of losing Tom Hiariej for the rest of the A-League season with a groin injury.
Hiariej was subbed off late in last month's 1-0 win over Wellington in pain and sat out last weekend's 3-1 loss in Perth.
The Dutch midfielder has seen a specialist to determine the extent of the injury and coach Paul Okon is sweating on the prognosis.
"Tom is a very important player for us. I think everyone has seen that this season," Okon said.
"We're awaiting news from the specialist as to how long it'll be and, if in fact, he'll be back this season.
"At the moment, we're anxiously waiting."
It comes before the ninth-placed Mariners travel to fourth-placed Melbourne Victory on Saturday night, eager to restore some pride after a largely underwhelming campaign.
History suggests they won't triumph at AAMI Park, given the Gosford side are winless in 14 matches against Victory.
The hosts will also be riding the momentum of Tuesday night's stirring Asian Champions League defeat of Kawasaki Frontale, along with the re-signing of coach Kevin Muscat.
But Okon said statistics didn't speak for everything.
"Both games this season, we've probably matched up against them and felt, in the first game at home, we should have won," he said.
"AAMI Park is not an easy place to go and Victory will be on a high after a great result midweek in the ACL.
"We know the challenges are there ... but we'll be going down there confident we can perform."