Shinji Kagawa has signed a new three-year contract at Borussia Dortmund, with his old deal having been due to expire next summer.
Japan international Kagawa committed himself to Dortmund until 2020 just hours after the Bundesliga club touched down in Tokyo for the first leg of their Asia preseason tour.
"Shinji closely identifies with our club, with the city, and with our fans," sporting director Michael Zorc told Dortmund's official website.
"And as one of the more experienced members of the squad, he is an unbelievably important anchor in a team which is very youthful overall."
At a news conference attended by more than 150 Japanese journalists, Kagawa added: "BVB, with its unbelievable fans, have really grown very dear to me.
"I am very glad that I will remain a part of this incredible club in one of the best leagues in the world with the highest viewing figures."
Kagawa joined Dortmund as a youngster in 2010, and following a two-year stint at Manchester United, he returned to the Westfalenstadion in 2014.
He has won two Bundesliga titles and two DFB Pokals with the club, for whom he has made 184 appearances and scored 54 goals.