Borussia Dortmund want to sign Ian Maatsen on a permanent basis but are reluctant to meet Chelsea‘s £35 million ($44.7m) valuation, sources have told ESPN.

The 22-year-old joined Dortmund on loan in January and became a key member of Edin Terzic’s team, playing every minute of their seven Champions League knockout matches which culminated in last weekend’s final defeat to Real Madrid at Wembley.

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Prior to that game, Maatsen publicly admitted his future was uncertain and sources have told ESPN that Dortmund are keen to extend his stay in Germany after the full-back made 24 appearances across all competitions, scoring three goals.

Chelsea are looking to recoup money through outgoing transfers to maintain compliance with the Premier League‘s Profit and Sustainability Rules and are willing to allow a number of fringe players to leave the club including Maatsen, Romelu Lukaku and Trevoh Chalobah.

However, sources have told ESPN that Chelsea’s hopes of securing a lucrative deal for Maatsen’s transfer is considered a stumbling block with Dortmund believed to be readying an opening offer considerably lower than that figure. One source suggested their initial offer would likely be between £20m to £25m.

Any deal that Chelsea want to form part of their 2023-24 accounting year must be completed by June 30 and Dortmund are hopeful that theoretical deadline could help them negotiate a lower transfer fee.