GRAHAM Arnold is “nervous for the families” of Western Sydney defenders after confirming the club made a pre-derby approach to sign Sydney FC’s first-team backline.

The Wanderers this week sought to open contract negotiations with centre-backs Alex Wilkinson and Jordy Buijs and full-back Michael Zullo, all off contract at the end of this A-League season.

The move is a sign new Wanderers coach Josep Gombau is already planning squad changes to better suit his playing style, having inherited personnel recruited by predecessor Tony Popovic.

Arnold returned serve ahead of Saturday night’s Sydney derby clash, implying the Wanderers’ back four couldn’t count on a job next campaign.

“They’ve done what you can do by the law. I’m very flattered they want nearly our whole backline,” Arnold said on Friday.

“I’m nervous for the families of their players, if their players are getting that signal this early that they’re after our backline.

“I also know a lot of other teams are looking at our players all around the world when they see what they’re doing, as well as the staff. “They’re well within their rights, but to go down that path is maybe a little bit early.” Off-contract players are allowed to talk to other clubs from December 1 though potential suitors must submit an official request, hence the intriguingly timed approach.

Arnold was confident Zullo, Buijs and Wilkinson would be going nowhere, with the latter understood to have a trigger built into his contract for an automatic extension.

Arnold added the last few days have brought “a lot of interest from outside” the A-League in his championship-winning players, who last month completed the domestic set with the FFA Cup trophy.

But he was not bracing for any departures like new Socceroo Matt Jurman’s move to South Korea, unflappable in his insistence his entire squad was intent on chasing back-to-back titles and contesting the Asian Champions League. Nevertheless, the Wanderers’ move adds further heat to this season’s second derby at ANZ Stadium, especially given they languish in ninth while Sydney sit five points clear at the top.

While Gombau considers multiple fitness issues including that of star striker Oriol Riera (hamstring), Arnold’s main concern is fellow marquee man Milos Ninkovic (calf).

The Johnny Warren Medallist will be given until kick-off to prove his fitness but, in the slim possibility he does play, would almost certainly start on the bench.

“Probably, because (David) Carney is doing so well - he and Adrian (Mierzejewski) have just been fantastic.

“We won’t risk him (Ninkovic) for one game with another 17 to go, but he’ll be training full today.”

While speculation about the Sydney players’ futures will ramp up, Arnold has ruled out Tim Cahill joining the club.

The Socceroos striker left Melbourne City to find a club where he can earn more game time ahead of the World Cup.

But Arnold said Sydney won’t be making an approach.

“Timmy’s a legend. He’s a fantastic guy. He’s made a decision that’s right for Timmy - to make sure he’s ready for his fourth World Cup,” he said.

“But here at Sydney I’m happy with what we’ve got.

We’ve got fantastic players up front... I’ve had no contact anyway.

“Timmy’s made his decision and it’s one that’s right for him no doubt... We’ve got what we’ve got. We’ve got no money in the [salary] cap.”