The Japan international failed to thrive at Old Trafford since his 22 million euro move from Signal Iduna Park to the Premier League two years ago and rumors have been rife all summer that he would be returning to the Bundesliga.
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Dortmund confirmed the move for an undisclosed fee — reported to be 8 million euros — with one day until the closing of the transfer window and BVB sporting director Michael Zorc says the club leapt at the opportunity to bring the player back.
"The chance presented itself in the past few days to sign Kagawa from Manchester United for the first time ever," Zorc told the club's official website Sunday. "Of course we opted to bring the enormous talent back to us to win more trophies."
"Shinji Kagawa is a technically gifted creative player who can determine the match in an instant," Watzke said. "He wanted to return to Borussia Dortmund and we are sure that — given the right rest, time and appreciation — he will get back to the level he was at two years ago."