DOHA, Qatar -- For several years now, the Bundesliga has enjoyed a symbiotic relationship with Japanese football players.
For many a prospect coming out of Japan, the German league has just been the perfect platform for them to make a move to Europe.
Since Yasuhiko Okudera became a trailblazer when he signed for Cologne in 1977, a total of 38 Japanese have featured in the Bundesliga.
So, with eight players of the Japan side for the 2022 FIFA World Cup currently plying their trade in the Bundesliga, will this inside knowledge prove to be a secret weapon for their Group E opener against Germany on Wednesday?
It will obviously help.
"Since we knew that we were going to play against Germany, I started to analyse the strikers a lot but, of course, playing against them is much better for analysing than just watching video," said the Samurai Blue captain.
"So, it has been a great experience and one of the reasons why I came to the Bundesliga -- to understand German football, German culture and German opponents.
"There are many Japanese players playing in the Bundesliga so we try to give a lot of information (to the rest of the team) and we understand what good qualities Germany have."
Knowing how good Germany is will be one thing. Being able to stop them is a completely different proposition altogether.
So perhaps, more beneficial than having some sort of insider knowledge of their upcoming opponents is the fact that German football has been helping Japan prepare for exactly a tough task like this.
Endo, who began his career as a fullback, is now close to being a complete holding midfielder as captain of Stuttgart.
After a spell filled with highs and lows playing for PSV Eindhoven, Doan has rediscovered his consistency -- and the smile on his face -- since moving to Freiburg in the summer.
But perhaps no one in the current Samurai Blue outfit is thriving more in the Bundesliga at present than Daichi Kamada, the Eintracht Frankfurt man who is looming as one of the biggest threats to Germany on Wednesday.
In 22 games so far this season, Kamada has netted 12 goals despite playing primarily in central midfield with many of his strikes proving to be pivotal in the Bundesliga, DFB-Pokal and even the UEFA Champions League.
Although he signed for Frankfurt way back in 2017, he initially had to bide his time -- and even spent an entire season on loan in Belgium -- before finally being given his chance.
With every season that has passed, Kamada has grown in influence for one of German football's proudest clubs. For now, his immediate task at hands is to break the hearts of the Frankfurt faithful whose allegiances have now switched to the German national team for the World Cup.
Of course, having a detailed insight into specific opponents or a style of play that they will come up against when they take on Germany on Wednesday will be tremendously useful for Japan.
But perhaps the not-so-secret weapon -- given they all ply their trade in the Bundesliga -- are the plethora of players the Samurai Blue can call upon that have German football to thank, for honing their craft and preparing them with the necessary expertise for exactly such a massive occasion that is a World Cup tie against the four-time champions.