In an interesting subplot, the Red Devils have also reportedly insisted that any further discussions between the two clubs will also involve them making a move for Madrid’s world-record £86 million forward Gareth Bale.
The Welshman is believed to be unsettled at the Bernabeu despite enjoying great success last season, and United are keen on making him their marquee signing in the summer.
De Gea has arguably been United’s best player this season, pulling off a series of impressive performances between the sticks, and will now have to choose between returning to Spain or staying put in Manchester on a hugely-improved £200,000-a-week contract.
The Red Devils suffered their third successive league defeat at home against West Bromwich Albion on Saturday, which leaves them just four points ahead of fifth-placed Liverpool.
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