Borussia Dortmund CEO Hans-Joachim Watze are inviting offers for Nuri Sahin.
The Turkey international is interesting Manchester City, Manchester United and Chelsea.
"We have already tried to extend his deal," Watze explained to Bild.
"Unfortunately this has still not yet succeeded. If Nuri [Sahin] gets an offer from Real Madrid or Barcelona, he has every right to talk about it with us. Then we will sit down with him and discuss it.''
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