The history of sporting tournaments is littered with tales of players and teams who broke a glass ceiling but ultimately fell away before the summit was attained. The lesson seems to be that the fairytale, captivating as it may be, rarely has a happy ending.
There are exceptions to the rule: Boris Becker winning Wimbledon as an unseeded 17-year old, Greece claiming the 2004 European Championship, Leicester City securing a shock Premier League title in 2016. It can happen.
For Japan to join that exclusive club, they will have to see off five so-called Tier One sides at this World Cup. Two, Ireland and Scotland, have already been accounted for. Next up is a South African side that most expect will bring the hosts' dream to an end when they meet in Tokyo.
Japan know this. They will understand that, for all the acclaim that has swept their way this last month, very few observers, informed or otherwise, expect them to go any further, but there is a determination and a belief in the camp that this Sunday's quarter-final will not be the last chapter.
“We are very privileged to coach this team,” said Scott Hansen, the defence coach who is to return to New Zealand to work as an assistant to Scott Robertson at the Crusaders after this tournament. “This team is very passionate about representing Japan.
“They understand the responsibility they have to, we hope, inspire a young generation of young Japanese players, boys and girls. Every day we come together and talk about being confident in our game. We feel that, on our day, our game has the ability to beat anyone in the world.”
Japan have captured the imagination of their nation and the wider rugby world with the beauty of their attacking rugby. They have brought an effervescence to their game that is bewitching to watch and increasingly difficult to counter but it is only one string to their bow.
Their bald defensive stats are nothing exceptional. Of the eight quarter-finalists only Wales and Australia have conceded more points and the Welsh more tries, but there has been a feverishness about their tackling and line speed that fits in perfectly with their manner of attack.
Added to that is a disciplinary record that has been exemplary. Japan have earned no cards of either colour. None of their players has been cited for any reason and both Ireland and Scotland did subject them to extended periods of defence in Pool A.
“We are well aware of how the referees will govern the games,” said Hansen. “Through all our camps in Miyazaki and all our focus leading into the World Cup we were instructing the players around tackle technique and tackle efficiency.
“We continue to drive that each week. It is a huge focus for us. In regards to the World Cup, there has been a lot of cards issued and at this stage we have been lucky enough not to be a man down because of it. We continue to work on that.”
Hansen has tweaked Japan's defensive tactics week by week depending on who the opposition are and what they bring. Against Ireland it was a commitment to two-man tackles that his players spoke openly about prior to the win in Shizuoka.
South Africa will be another test again.
“We understand that they have got a big forward pack. They have got a focus on their maul and their scrum and so they should because they are brilliant there. We also understand that they are going to use the ball in the air to influence the game.
“They have got a beautiful kicking game with a great kick-chase and regain. We understand that's coming so the challenge is there for us to influence it. But this morning, when we presented to the boys around that, it was 'this is what they do and this is what we need to do'.
“We are always going to try and focus on what we can do well and how we can influence the game.”
It has taken them this far.