Chelsea's protracted pursuit of the Germany winger André Schürrle from Bayer Leverkusen is effectively on hold while the Bundesliga club actively seek to secure a replacement, with their first choice, the Londoners' Kevin De Bruyne, keen instead to join Borussia Dortmund.

Schürrle was expected to complete the formalities of a £20m move to Stamford Bridge immediately after the end of the season, having agreed terms with the Europa League winners. But the move was subject to Leverkusen signing a forward to take the 22-year-old's place next season, with De Bruyne long established as their favoured candidate.

The young Belgian, whom Chelsea bought from Racing Genk for around £7m in January 2012, has yet to play for his parent club having been loaned back to his former side and then, last summer, to Werder Bremen.

His displays there this season – he has scored eight times in 32 appearances – alerted Leverkusen, now under the sole management of Sami Hyypia, to his qualities but have also impressed Dortmund, with the Champions League finalists understood even to have agreed a five-year contract in principal with De Bruyne's representatives despite not, as yet, having settled on any fee with Chelsea.

The London club had always envisaged retaining the 21-year-old forward and were prepared only to loan him out again, though Dortmund's interest will test that resolve, particularly if the player expresses a desire to leave.