A hero in the eyes of the Borussia Dortmund faithful, bundesliga.com looks back on what has made Japan megastar Shinji Kagawa such a popular figure at the club.

Few people, least of all Kagawa, will have known what to expect when the fresh-faced attacking midfielder arrived at Dortmund in the summer of 2010.

The then 21-year-old was the club's fourth and final signing of the close season, following the arrivals of goalkeeper Mitchell Langerak, full-back Lukasz Piszczek and another young attacker who was moving abroad for the first time – Lech Poznan’s Robert Lewandowski.

Kagawa was highly rated in his homeland, having helped Cerezo Osaka return to the J League by plundering 27 league goals in 2009. He had also graduated from Japan’s Olympic team to the senior squad and Dortmund made their move once he had netted seven times in 11 matches in the Japanese top flight.

At the time the 1997 European champions were rebuilding under Jürgen Klopp, having finished fifth and sixth in the German’s first two seasons in charge. "The first training was very tough," Kagawa said when he was unveiled by the club. "I can’t say yet how long it will take before I get used to the physical game here in Germany. But I think that I will adapt to it very quickly and also establish myself in the team."

Watch: Shinji Kagawa on Dortmund's global fan base

The new recruit’s faith in his own ability was entirely justified.

Kagawa scored his first Bundesliga goal for Dortmund in his third appearance, a 2-0 home win over 2009 German champions Wolfsburg. The bargain signing became an instant hit with the fans after a double in a derby win at Schalke a week later and by the winter break, he had eight goals in 18 matches.

The number 23 helped Dortmund become winter champions but his progress was halted after breaking a bone in his foot at the Asian Cup that January. When the Japanese star returned as a late substitute on the final day of the season, however, Dortmund had already been crowned as German champions for the first time since 2002.

Watch: Kagawa's top five Bundesliga goals:

Kagawa’s second year was even more successful. He again finished as Die Schwarzgelben’s second top-scorer, weighing in with 13 goals during what proved a thrilling title race with a rejuvenated Bayern Munich.

The bulk of those goals came at home – further enhancing his reputation with the fans – and his vision produced nine precious assists as Klopp’s side successfully defended their title. To cap a remarkable campaign, Kagawa also pounced for the opening goal and set up the crucial third as Dortmund thrashed Bayern 5-2 in the DFB Cup final. It was the first time the club had completed the domestic double.  

But Kagawa was the one major departure from Dortmund in the summer of 2012 – joining Manchester United for a fee of €22 million.

Kagawa left the Bundesliga only briefly, delivering on his promise to return to Dortmund.

Though he found things a little more difficult in England, the man from Kobe still helped Sir Alex Ferguson win one more league title at Old Trafford. Kagawa scored six goals in 20 games in his first season with United but found his opportunities limited the following year once Ferguson had retired.

The mercurial midfielder had vowed to return to Dortmund in the future and in August 2014, on transfer deadline day, he was welcomed back with open arms. "I wanted to fulfil my dream of playing in the Premier League," Kagawa said. "Now I am simply delighted to be back in Dortmund with this fantastic team and setup and these unique fans.

"BVB is like a family. I am proud that they did not forget me and that I can belong to it once more."

Watch: Kagawa makes dream return:

Trust the man for the big occasion to score in his first game back – a 3-1 win over Freiburg – and that trend continued in 2015/16. Kagawa netted in a home win over Schalke and in April he came off the bench to mark his 100th Bundesliga appearance with the equalising goal in a 3-2 success against Werder Bremen.

A wonder strike followed a week later in a draw at Schalke and Kagawa ended his second season back with nine league goals and seven assists. The 2012 Asian Footballer of the Year did not featured as much in 2016/17 with his brace in the 8-4 UEFA Champions League hammering of Legia Warsaw being an obvious highlight.

But considering he is still just 28, there is no reason why one of Dortmund’s best ever imports cannot help write more memorable chapters in the history of the club.

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