Since leaving Galatasaray in 2011, the Socceroos skipper has struggled to find a permanent home and has only managed short-lived stints at UAE clubs Al Jazira and Al Wasl as well as Sydney FC and J.League outfit Omiya Ardija.
But the 35-year-old is now training with English Championship side Blackburn Rovers, a club he represented with distinction over six seasons in the Premier League.
And while they may not be playing in the country's top flight at the moment, Postecoglou thinks Neill could benefit from playing for Blackburn if the club he used to captain decide to sign him in the current transfer window.
"It'll depend on form, whoever's playing I'll have a look at," Postecoglou said at Federation Square on Thursday.
"If they're playing well, whether that's in the A-League, whether that's in Europe, Asia, wherever that may be, I'll be looking at individuals' form, how they're going and their fitness and they're the key things I'll be looking at.
"To me, that's more important than the competition they're playing in."
Postecoglou said Neill had an important decision to make with regards to his immediate playing future as the Australian skipper continues his search to play regular football in a bid to strengthen his claim for a spot on the plane to Brazil.
"I really need players playing and fit around selection time so for Lucas... there's some pretty big decisions to come up," the Socceroos coach said.
Tom Rogic is in the same boat as Neill, according to Postecoglou, as the prodigious 21-year-old struggles for regular game time at Scottish Premier League club Celtic.
Although Postecoglou insisted he does not talk to his players about potential transfers, he made it clear he would prefer Rogic to look for a move somewhere else in the lead up to Brazil and said he would have no qualms urging Celtic manager Neil Lennon to help facilitate that.
"I'm hoping over the coming weeks that a decision is made," the two-time A-League championship manager said.
"He is at a fantastic football club but the reality of it is in a World Cup year he needs to be playing so if that means going somewhere else, as a national team manager I'd be much happier with that.
"I'll get my message across (to Lennon), yeah."
Postecoglou is set to embark on a tour of Oman and Europe to look at prospective candidates for the World Cup squad and the former Melbourne Victory manager said he was heartened by how well Australian footballers were performing around the globe.
"I'm still looking for consistency in players in putting in top-level performances in the A-League... and the same with abroad," he said.
"But the pleasing thing is that quite a few of them are now starting to put in some really good performances."
Meanwhile, Postecoglou denied he would use the World Cup merely as a building block for the 2015 Asian Cup given how unlikely Australia are to succeed in Brazil with powerhouses Spain, the Netherlands and Chile all in their group.
"This could be my only shot at a World Cup and I'm not going to give it away for anything and I don't think we should as a nation," Postecoglou said.
"If we want to do well at the Asian Cup, we need a strong World Cup to build a foundation through."
