The Netherlands stretched their longest-ever unbeaten streak to 23 games with a 2-1 victory over Slovakia on Monday that has set up a FIFA World Cup™ quarter-final against Brazil or Chile. But coach Bert van Marwijk said his team needed to be more assertive and bury the goal-scoring chances that come their way.

Against Slovakia, the Dutch sat back on a 1-0 lead thanks to a 18th-minute goal by the returning Arjen Robben. The Slovaks, shock victors over defending champions Italy in their group, had a handful of opportunities to draw level before Wesley Sneijder put the game out of reach in the 85th minute, the eastern Europeans claiming a consolation Robert Vittek penalty with the last kick of the game.

"We deserved to win by far," said van Marwijk. "There were phases when Slovakia could have got an equaliser, and when we should have been three or four up. The quarter-final will be a enormous challenge."

Van Marwijk added: "Our last pass was not good. It was really lacking in the first half. In the second half we had the best spell of the game and should have buried our opportunities. If you don't score a second goal, the game remains exciting. Our second goal finally decided the game."

Van Marwijk singled out goalkeeper Maarten Stekelenburg for helping to keep the Slovaks at bay. Having spent the first hour not having made a save of note, the keeper produced two fine efforts in quick succession to parry away shots from Miroslav Stoch and Vittek.

There were phases when Slovakia could have got an equaliser, and when we should have been three or four up.

Bert van Marwijk, Netherlands coach

"Maarten saved us in goal, but until his saves, Slovakia were not really dangerous," he said, adding that the Dutch had serious trophy intentions. "We're here for one reason and one reason only. As sportsmen, we want to go for the big prize. We're at the World Cup and want to be a winner.

"We're ranked third in the world and we've shown in the past we can win and that's what we're showing here. You just can't become world champions but I think people are taking account of the Netherlands."

Van Marwijk also hailed the return of Robben, the Bayern Munich winger who missed the two opening group matches because of a hamstring injury before finally playing a 20-minute cameo against Cameroon and starting against Slovakia.

"I'm pleased he's fit again," the coach said. "He's decisive for us. [With his injury] he was not the man he used to be. There was a little bit missing because of the uncertainty, the fear. "It's very important he played for 70 minutes. He's passed through that threshhold. It helps give us enormous opportunities up front, with a lot of speed and creativity."

Robben, who latched onto a deep Sneijder ball before cutting back and powering in a low shot past Slovak keeper Jan Mucha, said that he had felt no ill-effects from his injury.

"I was in general pretty free. I'm not yet at my top level but I was pretty confident," he said. "It was good to be on the pitch from the first minute and be decisive. It was a very difficult match. We didn't play our best game today, but it's about winning and going through. We'll save our best game for when we need it."

He added: "In the past people have said that the Dutch team play nice football but never win anything. We know that and want to change that. In EURO 2008 and the 2006 World Cup, we went through tough groups but then lost the next game."