The Socceroos have vowed to regroup and take inspiration from reserve goalkeeper Brad Jones' bravery after the family tragedy which looks certain to force him out of the World Cup.

The close-knit Australian camp was rocked by the news that Jones' four-year-old son Luca is seriously ill - something that undoubtedly affected their performance in their 3-1 friendly defeat by the United States on Saturday.

The popular Middlesbrough keeper appears certain to quit the World Cup to remain at his son's side in France as he battles leukaemia.

Skipper Lucas Neill, one of several Socceroos with young families, admitted the news had put the World Cup in brutal context and affected the players.

But before leaving South Africa on Saturday night, Jones had urged his Socceroos teammates to focus on doing their best for their country - and Neill promised the Australians will do just that.

"It hurt everyone badly, but we have to move on," Neill said from the Socceroos' new base at the five-star Kloofzicht Lodge resort outside Johannesburg on Monday.

"We have to use his story as an inspirational tool to drive us on that little bit more.

"Our thoughts are with him, but we must focus now on the World Cup. We have a job to do."

Striker Josh Kennedy said the squad had been heavily shaken by the news, but were committed to steeling themselves ahead of their World Cup opener against Germany on Sunday (Monday AEST).

"It brought us all back down to earth. We are all family, so we are all feeling for him, but we still have a job to do," Kennedy said.

Jones' message to his teammates as he departed South Africa was: "Keep going and do what you have to do."

The Socceroos and the sport's world governing body FIFA will give Jones time to decide whether he wants to officially withdraw from the tournament.

On Monday, FIFA gave official approval for Adelaide United's Eugene Galekovic to replace Jones in the squad should the Middlesbrough goalkeeper pull out as expected.

Australia have been given until 24 hours before their first match against Germany to make the switch.

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