The Dutch, among the favourites to win the trophy after a perfect qualifying campaign and excellent form in their warm-up matches needed an own goal - initially credited to Simon Poulsen but later amended to team mate Daniel Agger - just after half time and a tap-in from Dirk Kuyt in the 85th minute to triumph.
The Danes, who surprisingly included Nicklas Bendtner in attack after he looked set to miss the match with a groin injury, rarely threatened and in the end only the woodwork and some desperate defending saved them from a heavier defeat.
"In the second half we started with a lucky goal, so it was up to Denmark to come out but they didn't have the conviction or the force to," said Netherlands coach Bert van Marwijk.
"Then we scored the second and then you could see how well we can play. We could have had another one or two goals."
TOO STRONG
The Dutch, even without inspirational winger Arjen Robben, who is expected to return for their second match against Japan after a hamstring injury, were just too strong for the Danes whose fabled "dynamite" play never exploded into life.
"It was a deserved win for the Dutch," said Denmark coach Morten Olsen. "It could have been different if the (own goal) hadn't happened... but this happens in football. After that the Dutch were in a position they liked."
Netherlands did not play particularly well but with skipper Giovanni Van Bronckhorst commanding in his 100th international at the back, and Mark Van Bommel working tirelessly in midfield, they always looked sharper and quicker than the opposition.
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Wesley Sneijder, Rafael van der Vaart and Robin van Persie, three of their so-called "Big Four" attackers in the absence of Robben, did just about enough without really impressing and the Dutch always had the upper hand.
OWN GOAL
They took the lead when Poulsen, one of three Dutch-based players in the starting line-up, misdirected a header from Van Persie's cross on to the back of fellow Dane Daniel Agger and the ball went in for the first own goal of the tournament.
Sneijder saw a shot loop off Agger onto the bar in the 82nd and three minutes later Kuyt put the game beyond Denmark when he followed up to tap home after substitute Eljero Elia, who had a big impact, hit the post after a through ball by Sneijder.
Denmark, who have not beaten the Dutch, apart from a penalty shootout victory in Euro 92, for 43 years, rarely looked like scoring in a match that never really lived up to expectations.
The Danes seemed content
