Van Marwijk won't publicly detail his plans for Australia's crunch World Cup game against Denmark on Thursday.

If the Socceroos lose, they'll be knocked out of the tournament at the group stage regardless of the outcome of their last game, against Peru next Tuesday.

Beat the Danes, or draw, and they'll remain alive.

So how much will van Marwijk change Australia's tactics from the tournament-opening 2-1 loss to France?

"You can ask me those questions a thousands times, but I will not answer," van Marwijk said.

Okay. Tell us your impressions about the Danes then?

"I have to do that with the players," he said.

"I will not tell everybody what I think about Denmark."

What about the approach of Peru in their 1-0 loss to the Danes in their tournament opener. Any lessons for you?

"I don't know," van Marwijk said.

"I see a lot but I always try to concentrate on my own team."

But is there anything in the Peruvian approach that the Socceroos can adopt?

"You cannot compare that ... I am not a magician," he said.

How about young wizard Daniel Arzani then? Is he ready to break into the starting line-up?

"Every player in the squad is capable to start," van Marwijk said.

"Even Tim (Cahill) can start but he ... cannot play the whole game."

Can Arzani?

"Then you will translate that, and you will write that maybe he will play," he said.

"You can ask me again. But if you ask those questions too much, I will not give any interviews again.

"I like to talk about football for hours, when it really is about football.

"But when I get the same questions over and over again, and you say (them) in a little different way, I say ... don't bother me."

Australian Associated Press