Robin van Persie admits Holland face a challenge of expectation after their stunning victory over Spain as they prepare to take on Australia.

Louis van Gaal's side routed the defending champions in their World Cup opener, giving full value for a 5-1 victory that might have easily been embellished further as the Dutch tore their opponents apart.

Van Persie and Arjen Robben each scored twice, turning in irresistible attacking performances that defied their status as underdogs going into the match.

That is a tag they can forget about for the remainder of the tournament, having produced the performance of the competition to date.

They will now be expected to brush aside Australia at Porto Alegre on Wednesday and Van Persie accepts that his side must now deal with being among the favourites.

"Everybody is euphoric and happy in the Netherlands. We are dealing with people's expectations here, which had been low compared to other years," he told FIFA.com

"I actually think this worked to our advantage because nobody expected much from us. But after such a performance, the dynamics have naturally changed. However, as a country, we shouldn't get ahead of ourselves. We have to stay realistic."

The Manchester United striker, whose athletic header to make it 1-1 against Spain is destined to go down as a defining moment of the World Cup, stressed the need for cool heads to counteract the inevitable hype.

"The tournament has barely started yet. We achieved an impressive result but we have a long way to go to win this tournament.

"This is my fifth [major] tournament and I know how these things work: the euphoria vanishes just as quickly as it appears. So we have to make sure that we hold on to it - not only for the people and fans, but also for ourselves."

The Socceroos lost their opener 3-1 to a vibrant Chile and need a result to stay alive in the competition.

It is a big ask for them to tame L'Oranje but veteran midfielder Mark Bresciano expects Australia to have learned lessons from their first match in Brazil.

"For a lot of guys this is their first tournament like this and we were not all there at the beginning," he said.

"Against Chile, we gave it away in the first 20 minutes. Now we have all experienced how it is here and against the Dutch we will just stand up from the first minute.

"We can hope they have a bad day and that we can benefit. We must be ready to take any small chance and function well as a team."