David de Gea
David de Gea will be a free agent next summerGetty Images

Manchester United midfielder Ander Herrera insists nobody knows whether his compatriot David de Gea will secure his desired move to Real Madrid before the end of the transfer window. The Spanish midfielder says that the situation is completely out of his hands but admits his staying would be a huge boost for the Premier League giants because he is "the best in the world".

De Gea has been linked with a move to the Santiago Bernabeu since the beginning of the summer after he rejected an offer to extend his current Old Trafford contract, which is set to expire next summer. The Spaniard has been United's best player during the last two campaigns but is likely to return to his homeland where his girlfriend lives.

However the clubs have failed to reach an agreement for his services during the summer because Los Blancos don't want to pay big money for a player that could join them for free at the end of this season. Nevertheless Spanish newspaper Marca claimed earlier this month that Real Madrid are confident of securing his services this summer, although they are reluctant to meet United's £29.1m valuation for the keeper.

United manager Louis Van Gaal claimed last week that even though the keeper has been left out of the squad for the first games of the campaign owing to the speculation about his future, the club are not likely to sell him before the transfer window closes on 1 September. "I think when Manchester United wants a player he shall come, besides when a club isn't selling. It is the same with us. We are not selling de Gea," the manager claimed.

Herrera has now suggested that even the United players don't know how the transfer saga will end. "I understand that there is an uncertainty among you [the journalist]. There is also [uncertainty] between us because we do not know what is going to happen. We have to wait," he told Spanish radio station Cadena Cope.

"He is calm. One of his best skills is his serenity. He never gets nervous. That's why he is so good. The situation is out of my hands. I just can say that for me he is the best in the world, so if he stays with us it will be phenomenal."