Liverpool, Manchester City and Manchester United are all interested in the teenager. However, a summer deal is widely thought to be more likely.
Barnard is excited for the prospect of Chelsea travelling to play Dortmund for the first time. And he hopes to get some advice from City on how to play their German opponents.
Barnard added:”Dortmund is one team that we’re yet to play in the Champions League, so we’re looking forward to going there. Man City were in their group so we hope to be talking to our friends at City to get a little bit of insight into Dortmund from that point of view.”
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