In the modern game, the success of a transfer can depend not only on a player’s abilities on the pitch but also on his appeal off it.

One of the hardest, most elusive currencies in the today's football, social media popularity remains highly prized by football clubs when scouting the next new arrival.

Javier 'Chicharito' Hernandez's arrival at Bayer Leverkusen in 2015 prompted the club to set up a Spanish-language Twitter account, which peaked at over 100,000 followers. Similarly, James Rodriguez's move to Bayern Munich this summer increased the German record champions' already-impressive online following significantly.

With that in mind, then, the fact that Atsuto Uchida is yet to feature for Union Berlin will not matter too much to the second-tier capital club, nor to their legions of new supporters.

With close to 80 caps for Japan and having played every minute of his nation’s 2014 FIFA World Cup campaign, Uchida is a household name in his homeland and while boasting a huge online following, several other statistics also illustrate the sheer scale of his appeal even beyond the land of the rising sun.

Take, for example, Union’s tweet announcing his arrival from Schalke, which was retweeted almost 5,600 times, dwarfing the average interaction for the club’s Twitter posts. The full-back has driven huge amounts of Twitter engagement for Union since, too.

Indeed, Schalke’s official Japanese Twitter account remains the third-most followed among European clubs, behind Barcelona and Real Madrid only, despite Uchida’s departure after seven years this summer.

On our sister page, the Bundesliga's official Japanese site, Union Berlin are the third most-clicked club since the 29-year-old's arrival.

Not only was Uchida named in the 2012/13 Bundesliga Team of the Season, ahead of the treble-winning Bayern Munich captain Philipp Lahm, the Japan star also made the final four of the Bundesliga Idol in 2016 thanks to votes from his legions of fans - despite him not having played a minute that season through injury.

Perhaps most interestingly, when Uchida was at Schalke, Japanese users in their thousands ignored the language barrier to subscribe to Schalke TV, a pay-TV service where the entire on-boarding and payment process is conducted in German.

Watch: Schalke were one of several Bundesliga clubs to travel to the Far East this summer!

Of course, it should be noted that Union are not in the business of signing players purely for marketing purposes. Quite the contrary, in fact: Uchida has been acquired primarily for his footballing ability. (Following the departures of Emmanuel Pogatetz and Benjamin Kessel, the club were in the market for a new defender.)

The 29-year-old is well known by the coach Jens Keller, who mentored him at Schalke, and is excited by the prospect of the Iron Union gaining an unprecedented promotion to the Bundesliga.

Christian Arbeit, Union's head of communications, is more than aware of Uchida's huge appeal but insists that the club will not go overboard in "selling" their newest product, with on-field success - and promotion - remaining centre stage.

"We've picked up lots of new followers since we signed him, and we have enough shirts with his name on ready to sell, but we don't plan at the moment to make our website available in Japanese, for example, and there won’t be a special collection of Uchida merchandise to buy," said Arbeit. "What comes first for us is the team."

Atsuto Uchida warms up prior to Union's 1-1 draw with Arminia Bielefeld on Matchday 4.

There is no question that Uchida's arrival has contributed greatly to putting Union Berlin on the international map, however, and it feeds into the narrative that this cult club is growing in popularity year on year.

From organising carol-singing events at Christmas to allowing fans to place couches on the pitch to watch Germany matches, to automatically extending cancer sufferer Benjamin Köhler's contract back in early 2015, Union is a club run like a family. In Uchida, that family has now grown to include a nation with a population of 127 million people over 5,000 miles away.

Bernie Reeves

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