Van Marwijk's side put in an uninspiring display in Oslo, as Ola Kamara's hat-trick fired the home side to a convincing victory.

The Dutchman has been appointed to guide the Socceroos through to the end of the World Cup, with Graham Arnold set to take the reins upon their return from Russia after Ange Postecoglou walked away from the role in November.

Van Marwijk says the defensive lapses that aided the host's cause were an indication of the amount of work required ahead of the tournament.

"It's always difficult in the first game, we talked about it before," he said. "This is a situation where you have to get to know each other.

"It was clear that we are not ready yet and we need time to develop this team.

"I think when you see the game, you see that there are two standout situations where there are individual faults and some goals.

"That's a shame because it has nothing to do with how you want to play."

Taking some positives from his Australia experience so far, Van Marwijk added: "We are starting the preparation and everyone is full of energy and everyone wants to improve.

"That's positive, but I don't like to lose and 4-1 is too much."

Australia takes on Colombia at Craven Cottage in another friendly on Wednesday (AEDT).