Borussia Dortmund have signed defender Raphael Guerreiro from French side Lorient on a four-year deal until 2020, the German club announced on its website on Thursday.

The 22-year-old, who is currently on international duty with Portugal at the 2016 European Championship, made more than 100 appearances during his three-year stay with the Ligue 1 club.

"Raphael Guerreiro is a technically experienced player who is equally comfortable in several positions," Dortmund sporting director Michael Zorc told the club's website (www.bvb.de) "We are very happy that he has decided to come to Borussia Dortmund."

Guerreiro joins Turkish teenager Emre Mor and midfielder Sebastian Rode, who have already penned deals with last season's German Bundesliga runners-up.