Australia will line up against New Zealand at Adelaide Oval on Sunday and against Serbia at Etihad Stadium in Melbourne on Tuesday - and all eyes will be squared firmly on their younger brigade as it attempts to fill the sizable void left by the big-name trio.

But with qualifiers for the 2014 World Cup in Brazil rapidly approaching, the question is whether those three - so reliable over the years for the Socceroos - will figure in the tournament at all.

Kewell is 32 and clubless after failing to agree to a new contract with Turkish giants Galatasaray, while Cahill (31, Everton) and Schwarzer (38, Fulham) both battled injury towards the end of their English Premier League campaigns.

Age may be yet to weary them but many contend that it is only a matter of time before they are unable to keep up with the game at its highest level, while the next generation of talent waits in the wings.

However, Wilkshire expects them to wear green and gold for as their legs will keep them standing.

"Everyone's getting older - Schwarzy especially," Wilkshire laughed.

"But he's still around and they're going to be back. It's a couple of games - just the one camp that they're missing. They're still going to be around for a long time to play.

"It's still an opportunity for the young players to come through, step up and show they can play at this level. It's a void that someone needs to step up and fill."

The first opportunity to fill that void will be on Sunday, against a New Zealand side that was outplayed 3-0 by Mexico in Denver on Thursday morning (Australian time).

The All Whites gave the Socceroos an almighty scare in their farewell match at the MCG before last year's World Cup, taking the lead before Australia stole a 2-1 win deep in injury time.

This time around, the Kiwis are likely to have heavy legs given their arrival less than 24 hours before the game - but their recent record shows they may be a far more formidable opponent than their FIFA ranking of 56 suggest.

New Zealand's campaign in South Africa was incredible for a nation considered a minnow in world football, conceding just two goals to end the tournament as the only undefeated side - even though they did not reach the Round of 16.

Wilkshire said that the Socceroos could not wait to take on their trans-Tasman rivals.

"It goes without saying that Australia against New Zealand in any code of sport, whether it's football, rugby league or marbles - it's competitive and we want to win," he said.

"It's a friendly rivalry but they're going to want to knock us off. It's a scalp they'll want to take from us but we've got to make sure we don't let that happen."