Newcastle Jets will be without central defender Nikolai Topor-Stanley for tomorrow evening's round 3 clash with Perth Glory.

The 25-year old has been ruled out with a hamstring problem and his absence is expected to be felt by head coach Branko Culina who has not yet decided on who will replace the former Glory man.

"You can be as organised and disciplined as you like but when you lose a key player in a team and you don't have another one to replace him, there's always a little bit of concern," Culina told the Newcastle Herald.

"That's the problem you are always going to face during the course of the year and that's why it's important to have some depth in your squad, albeit not of the same quality."