Aberdeen have rejected a formal transfer request from central defender Scott McKenna, according to Sky Sports News.
The Dons have turned down a number of approaches in each of the last three transfer windows for the 22-year-old Scotland international's services, with QPR, Nottingham Forest and Stoke all having been keen to sign him.
Aston Villa also had a £7m offer for McKenna rejected in the 2018 summer transfer window, while it is believed Celtic had a substantial offer rejected in January as well.
However, McKenna feels now is the right time for a new challenge and is hoping to be able to leave this summer - although Aberdeen are so far refusing to do a deal.
Sky Sports News understands the transfer request was made to Aberdeen on Saturday, before Sunday's game against Hearts.
McKenna is contracted to the club until 2023, with Aberdeen due to fly to Croatia on Wednesday for their Europa League qualifier first leg against HNK Rijeka.
As it stands, it is unclear if McKenna will be on that flight.
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