Portuguese media outlet O Jogo, as quoted by the Daily Mail, is reporting that Sporting Lisbon are prepared to sell Fernandes in a £65m deal in order to clear their debt.
The same article states that Manchester United are keen to sign a creative midfielder to fill the void left by Ander Herrera and Marouane Fellaini over the past year.
According to the same story, the Red Devils could face competition from Tottenham Hotspur, given that Spurs are facing the prospect of losing Christian Eriksen.
Fernandes has scored five goals and has made five assists in 10 appearances in the Portuguese top flight this season to maintain his prolific form for Sporting.
The 25-year-old was linked to Manchester United and Tottenham in the summer after the Portugal international netted 20 times and created 11 goals in 33 games.
Manchester United and Tottenham have both made disappointing starts to the Premier League season to leave them well off the pace in the race to secure a top-four finish.
Champions League runners-up Spurs are in 14th place in the Premier League table and 20 points adrift of runaway leaders Liverpool FC.
Manchester United are two points better off than Spurs but find themselves in seventh position in the Premier League.
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