Australian head coach Ange Postecoglou brought World Cup heartache to four players, including playmaker Tom Rogic, in unveiling his definitive 23-man squad, saying Tuesday all his choices were meticulously thought out.

As Monday's deadline expired, Postecoglou had broken the news to a squad captained by midfielder Mile Jedinak that Rogic, Mark Birighitti, Josh Kennedy and Luke Wilkshire would be jettisoned.

Veterans Tim Cahill, Mark Bresciano and Mark Milligan meanwhile become the first players to represent the Socceroos at three World Cup tournaments, having been involved in the 2006 and 2010 campaigns.

Of the squad, seven play in the Australian A-League.

Postecoglou said he had thought long and hard about his choices -- which were unexpected, at least in the case of Wilkshire.

On the loss for fitness reasons of Rogic and Kennedy, Postecoglou told reporters he was "obviously very disappointed for both."

"(Rogic) was obviously struggling. We thought by having him in camp for the amount of time we did we could make some progress with him -- the medical people thought he was a chance and worked awfully hard.

"I think he knew after the first minute (of Monday's win over club side Parana) that he just wasn't right. He was pretty devastated last night (but) he walks away without having put up the white flag.

"Josh is a timing thing. He was due to play yesterday and we were quite happy with the way things were going" until he pulled up with a back problem.

"With the timing of it -- could be one week, two weeks. There's too much uncertainty there," said Postecoglou regarding Kennedy.

"All decisions were thought out. It's hard to travel all this way, got so close and have to go home - but that was the situation we were in -- I wanted as much time as possible to look at everybody."

He insisted he was confident in the ability of Ivan Franjic, now the only recognised right back after the surprise omission of Dynamo Moscow's Wilkshire, veteran of 80 caps.

Franjic comes to the event on the back of recent fitness problems following a knee injury suffered last week against South Africa.

But Postecoglou insisted: "He's had a great season with Brisbane -- he's missed the last three or four days because of a knock but that's not a concern for me. I'm confident he'll be in great physical condition.

"It's no secret we're light across the whole back four but at the same time we're pretty happy with the ones we have got in there.

"Looking at the make up of our squad there are other areas of the park we're going to need more flexibilty.

"We have had to weigh up form, fitness and squad balance," he explained.

"We've selected a squad that can do Australia proud and they will walk out onto the pitch for the World Cup in the green and gold shirt and display the characteristics that define our country.

"Our stated aim is to make our country proud, show the world what Australians are made of and test ourselves against the very best football players in the world and this group of players is capable of doing that."

The Socceroos face Croatia in Salvador on Friday in their final warm-up before meeting Chile on June 14 in Cuiaba.

The countries met in the 1974 finals, playing out a goalless draw in Berlin.

Australia final squad:

Goalkeepers: Mat Ryan (Club Brugge/BEL), Mitchell Langerak (Borussia Dortmund/GER), Eugene Galekovic (Adelaide United).

Defenders: Ivan Franjic (Brisbane Roar), Jason Davidson (Heracles Almelo/NED), Matthew Spiranovic (Western Sydney Wanderers), Bailey Wright (Preston North End/ENG), Alex Wilkinson (Jeonbuk Motors/KOR), Ryan McGowan (Shandong Luneng/CHN)

Midfielders: Mile Jedinak (Crystal Palace/ENG), Mark Milligan (Melbourne Victory), James Holland (Austria Vienna/AUT), Massimo Luongo (Swindon Town/ENG), Oliver Bozanic (Luzern/SUI), Matt McKay (Brisbane Roar), Mark Bresciano (Al-Gharafa/QAT)

Attackers: Tim Cahill (New York Red Bulls/USA), Dario Vidosic (Sion/SUI), Tommy Oar (FC Utrecht/NED), James Troisi (Melbourne Victory), Ben Halloran (Fortuna Dusseldorf/GER), Adam Taggart (Newcastle Jets), Mathew Leckie (FSV Frankfurt/GER).