Had you asked people in the street on the eve of Japan's first World Cup game if they thought they would beat Cameroon's Indomitable Lions, the answer would have probably been a resounding no. While humility is a quality for which the Japanese are renowned, it was resignation rather than modesty that fuelled the widespread predictions of a defeat against Cameroon, a country ranked 19th in the world to Japan's 45th.

Takeshi Okada's debatable management of the "Samurai Blue", and their run of four straight defeats in recent friendlies, had relegated the team as a good bet to exit after the group stage. Which is why Keisuke Honda's goal in the 38th minute – and Cameroon's failure to reciprocate – came as such a surprise, even at home.

According to an online poll of those who watched the game on television, 75% said they hadn't expected Japan to win. But they watched anyway, with the game pulling in 45.2% of viewers in Tokyo and the surrounding areas – the highest for any TV programme in the past four years.

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Some say that Japan's first World Cup win on foreign soil has sparked renewed interest in both football and the Samurai Blue team. The following morning, the ominous drone of vuvuzelas echoed down the streets of Tokyo's notoriously cramped neighbourhoods as recaps filled the airwaves. The Sankei Shimbun newspaper reported that package tours to watch the remainder of the tournament in South Africa were in demand.

While the game isn't viewed with the same tepid interest as it is in the United States, football in Japan, as on the other side of the Pacific, plays second fiddle to baseball.

"The international games are interesting, but to be honest I don't really watch the J-League [Japan's professional league]," said one fan, dressed in a replica shirt, as he and his girlfriend – who hesitantly admitted she rarely paid attention to football—went to watch the match against Holland on Saturday night.

Despite apathy towards the domestic games, World Cup fever seems to have caught on among some unlikely viewers. Before games, carefully manicured young women strut through the streets dressed in replica shirts, while nightclubs usually reserved for underground electronic music have been hosting sold-out World Cup parties. Casualties from the previous night's screenings – the second and third games begin at 11pm and 3:30am, respectively – can be seen on the trains the next morning.

Public viewings offer other possibilities: the "matchmaking support centre" of one city in the rural Nagano prefecture used Saturday's match to bring together would-be couples at an outdoor screening. "We're a small town, and there aren't many opportunities to meet potential dates or to watch the game outside of the home," said the centre's spokesman, Yoshihiro Yawata. "We wanted to take advantage of the event."

For all the attention Honda's goal received, few were deluding themselves about the result of Japan's game against Holland.

While the cover of the sports magazine Number had declared Japan's victory over Cameroon a "miracle", the Dutch were clearly a different proposition.

"Miracles can happen once, but not twice," said Kota Baba, a waiter at a beer hall, even as he stood watching Serbia pull off an unexpected win over Germany the day before Japan were to play Holland.

And it was in that spirit that people flooded into bars and pubs on Saturday evening dressed in Japan's colours – many wearing the former Japan international Hidetoshi Nakata's No7 shirt from World Cups past – to cheer on their cautiously optimistic heroes. Samurai Blue Park, a temporary event space run by the Japan FA, was packed to the gills, having sold out its 1,000 seats for the first time during the tournament.

In the end, the result was all too predictable, as Wesley Sneijder secured victory for the Dutch.

But Japan's fans were in a forgiving mood. Many praised the team's willingness to attack and were upbeat about Japan's performance against a side that stands 41 places higher in the Fifa rankings.

Though the domestic high from the Cameroon match has worn off, many remain hopeful that Japan will revel in their underdog status and advance to the knockout stage with a win over Denmark on Thursday.

Baba, though, is not so sure – and is already formulating a plan b. "Of course I'd like Japan to move into the next stage," he says, "but in the meantime I'll definitely be cheering for Argentina or the Netherlands."

This is not a news report and may contain views expressed by the author which are not supported by GNM.