Borussia Dortmund have confirmed the signing of German international Gonzalo Castro from Bayer Leverkusen. The midfielder joins BVB on a four-year contract through to 2019 for a fee of 11 million euros (12.1 million dollars).

"We are delighted to have signed an experienced, technically-gifted midfielder who can be used in many different positions," Dortmund Sporting Director Michael Zorc said on the club's website.

Castro, 27, joined Leverkusen as a 14-year old in 2002 and made 370 appearances for the club after progressing through the youth ranks. He has also made five appearances for the German national team.

Castro becomes the first signing of the summer for Dortmund, and the first new player to join the club ahead of Thomas Tuchel's arrival as head coach next season.