Ilkay Gundogan has been ruled out for up to six months following a knee injury earlier this month.
The 25-year-old dislocated his knee during training with Dortmund earlier this month and will miss out on Euro 2016 this summer.
The injury has also put a move to the Premier League in doubt and his own club have postponed contract talks.
The German newspaper Bild report that it will take Gundogan four to six months for him to make a full recovery.
Both Manchester City and Arsenal are interested in signing the midfield playmaker according to the Daily Mail newspaper.
Manchester Evening News report that the transfer was close to completion with City agreeing personal terms with Gundogan. The report goes onto state that it is unclear whether the injury will affect the Citizen’s plan to sign him over the summer.
Gundogan has seven assists and three goals in 40 appearances for Dortmund this season.