Matt Simon – Central Coast's leading A-League scorer for the past two seasons – may be forced to return from injury off the bench on Friday night.
Simon returned to full training this week after recovering from a minor back injury and is expected to be in Lawrie McKinna's squad when Perth visit Bluetongue Stadium in Gosford.
But McKinna may not use the fringe Socceroo striker from the start with rejuvenated Nik Mrdja a chance to retain his place.
Mrdja was called into start when Simon missed last week's 5-1 demolition of North Queensland and made the most of his opportunity, scoring two goals.
Mrdja has now scored three goals in two games and has also found the back of the net several times in the club's youth team.
"Nik did everything asked of him last week, he's looking very sharp," McKinna said.
"But Matt has been good for us for a long time, it's a tough call."
"It'll be a decision I'll make as late as possible."
After battling serious injury for much of his time at the Mariners, Mrdja is now fully fit and starting to show the form that made him one of the best strikers in the old National Soccer League.
"I always knew the boy had it in him," McKinna said.
"He's had some hard times but when he's on his game he can score goals. At the moment we've got plenty of options up front."
After struggling to find the back of the net the Mariners have netted nine goals in their past two matches.