The Dutch, tipped to do well in South Africa, were far from their fluent best and it took an own goal from Simon Poulsen to break the deadlock just after half-time.
Liverpool striker Dirk Kuyt made sure of the win five minutes from time and van Marwijk expressed his satisfaction with the points after the game.
Ã¢â‚¬Å“I’ve always said that this was the most important match because a good beginning to a world championship is so important,Ã¢â‚¬Â he said.
Ã¢â‚¬Å“Today, as you could see, there was a bit of tension with the players. It was difficult, but we won, which is the most important thing.
Ã¢â‚¬Å“You cannot afford to make many mistakes, but we played well, we didn’t give away too many opportunities and all the players should be complimented for that.
Ã¢â‚¬Å“In the end, we are really pleased with this win.Ã¢â‚¬Â
Meanwhile star-player Arjen Robben has rejoined the squad.
The Bayern Munich winger injured his hamstring in the warm-up win over Hungary last week but could be fit in time to face Japan in Durban on Saturday.
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