By Spain correspondent Miguel de Souza

Super-agent Jorge Mendes has been mandated by Real Madrid to broker David De Gea’s proposed transfer to the Spanish giants this summer, Football Insider sources understand.

Real have lined up the 24-year-old goalkeeper and are confident that he will continue to shun Manchester United’s attempts to persuade him to stay at Old Trafford.

With reports in Spain claiming that De Gea has already agreed personal terms with Real, United manager Louis van Gaal has admitted that the club are identifying replacements for the former Atletico Madrid man.

Football Insider has learned that Mendes, the super-agent who represents United duo Angel di Maria and Radamel Falcao, will broker De Gea’s expected switch to the Bernabeu.

Mendes will be involved in negotiations between the two clubs over the transfer fee and the structure of a deal that is likely to be one of the dominant sagas of the forthcoming window.

Real have identified De Gea as Iker Casillas’ successor and United fear they are losing the battle to tie the goalkeeper down to a deal that extends his contract beyond the summer of 2016. He has rejected a string of offers, with the latest believed to be worth a basic £220,000-a-week plus top-up bonuses.

Speaking on Friday, Van Gaal admitted that United have begun the process of considering replacements for De Gea in the event that he leaves Old Trafford this summer.

We know who already shall be the next goalkeeper,” the Dutchman said. “We have a list of goalkeepers who can replace him because we have to be organised also, not only for that position but every position. We want him to stay so hopefully he shall sign.”