They beat Denmark in their first Group E match with the aid of an own goal and this time benefited from a goalkeeping blunder by Eiji Kawashima that helped Wesley Sneijder's thumping shot on its way into the net after 53 minutes.
With highly-fancied teams like Spain and Germany having already tasted defeat, however, coach Bert van Marwijk was more than satisfied that they will be the first to reach the last 16 if Cameroon fail to beat the Danes later on Saturday.
"We came here to win a prize to become world champions now that's far from straightforward and easy," said Van Marwijk.
"If we can continue to show stability, and if we maintain confidence in really winning something, we might get far. So the target is to go for the prize."
"I would love to win with beautiful football, but you've got to deal with well organised opponents," he added.
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Japan, who upset Cameroon 1-0 in their opener, had gone out to frustrate their opponents but also attacked in numbers when they had the chance and will rue a string of missed chances, including substitute Shinji Okazaki blasting over late on.
"We expected the Netherlands to be frustrated but defence alone was not enough," said Japan coach Takeshi Okada. "So I told our players to be very courageous and aggressive when we had the ball."
Okada refused to blame Kawashima or the ball for the defeat despite the keeper misjudging Sneijder's winning strike.
"As for the Sneijder goal, it was a good shot," he said.
CAGEY AFFAIR
The first half was a cagey affair with Netherlands failing to exploit their domination of possession and mustering just three shots, midfielder Rafael van der Vaart's effort the only one to test Kawashima.
The Dutch came out firing after the break, however, and Robin van Persie had already wasted two chances before he seized on a loose ball in the penalty area.
With the defence closing him down, Van Persie slipped the ball to Sneijder on the edge of the box and the playmaker slammed his shot into the net off the keeper.
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"What you need is a bit of luck," said Sneijder. "And we ended up at 1-0 and I think, at the end of the match, we should have ended up with 2-0 or 3-0."
The goal did bring Japan even further out of their defensive shell and opened up the game but both sides conspired to squander the efforts they created.
Dutch substitute Ibr
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