“He’s a genius”. “A masterpiece”. “Our saviour”. “The miracle man”. These were just some of the words used to describe Louis van Gaal in the Dutch press following Holland’s quarter-final victory over Costa Rica.

In Dutch offices, many employees have a screensaver on their computer screens of the Christ the Redeemer statue with Van Gaal’s head on it. There is an online poll asking who is the best coach of the national team ever. Van Gaal is winning it even though he has reached only the semi-final, while other coaches (Ernst Happel, Rinus Michels, Bert van Marwijk) got to the final.

Things have changed quite a bit in Holland over the last few weeks. In February Hugo Borst, an influential journalist and former friend of Van Gaal, published a book called Oh, Louis in which he, and some of his sources, put him down as a narcissist. It is a common perception. In the popular Dutch football programme, VI Oranje, the pundits went as far as describing him as a complete nutcase before the tournament had started.

But the ones going crazy now are the fans back home, thanks to the team’s progress and the manager’s “new world” coaching style.

Did we – fans, media, experts in Holland – expect this? Not in a million years. The team is filled with players from the Eredivisie, a competition that keeps falling down on the international ladder. Feyenoord were kicked out of the Europa League by Kuban Krasnodar. The Johan Cruyff revolution at Ajax – that cost Van Gaal and his assistant Danny Blind their jobs four years ago – still hasn’t produced anyone such as Cruyff, Van Basten, Bergkamp, Sneijder, not even a Van der Vaart.

When it was clear the midfielder Kevin Strootman (Roma) would miss the World Cup, his injury was treated as a national disaster. Some blogs suggested the “selection of babies” were going to get hammered by Spain, Chile, maybe even by Australia.

Before the tournament started Van Gaal then decided to change the system to 5-3-2. That was like cursing in a Dutch church, for our football bible decrees we should always attack and play with wingers. Dutch fans don’t want a team who wait and counterattack. That’s for Germans, Italians and Belgians.

According to another pre-tournament poll, only 5% of the 17m population believed we could reach the final again. This was an extraordinarily low figure because the Dutch are famous for believing they are the best. The Oranje fans love to party with their carrot-heads, tulip-dresses and orange overalls with lion’s tails during matches. They are naturally optimistic, euphoric. For once heading to Brazil they weren’t, to put it mildly.

The sensational opening game against Spain changed the whole atmosphere. Viewing rates and social media exploded. Half of Holland suddenly believed the team could become world champions, a figure that is climbing after every match.

There are big parties on big squares organised to watch the games. Oranjefever is gripping the nation. In The Hague they are already planning a party for Tim Krul, the third goaliereplacementgoalkeeper who won the penalty shootout against Costa Rica. Suddenly the Dutch have got their Dutch courage back. People are already looking forward to the final against Germany and taking revenge for 1974 (the national trauma of losing 2-1). We know our big neighbour has more experience, more quality, more stamina, play better football; it seems like a hopeless mission. But everybody has faith because we have “Louis, the miracle man.”

Bart Vlietstra writes for the Dutch magazine Helden