The Spanish giants have long been linked with a move to bring the goalkeeper to the Bernabeu and he came within a whisker of signing for Real Madrid back in the summer of 2015, before the move fell through at the final hour.
The 27-year-old has been earning huge amounts of praise for his strong performances for Manchester United in recent months, with De Gea having helped the Red Devils to finish second in the Premier League table last term.
Real Madrid continue to be touted as a possible target for the goalkeeper, and Sunday Times reporter Castles has confirmed that the Spanish club do indeed retain an interest in one of Manchester United’s prized assets.
Speaking on the Transfer Window podcast, Castles said: “We need to keep a close eye on this one. This is a summer where Real Madrid are tearing up the squad.
“Florentino Perez needs to do something big. He knows De Gea sees his future at Real Madrid at some point. As long as his contract is not resolved, he becomes a guy they could have a go at.”
Meanwhile, Manchester United have already completed their first two signings of the summer transfer window after tying up deals for both Diogo Dalot and Fred.
The Red Devils are believed to be on the lookout for a number of other recruits this summer as they bid to build a squad capable of winning the title next season.
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