Manchester United and Arsenal have asked Porto to keep them informed of Raul Meireles' situation.
Marca says the ball-winning midfielder is interesting Real Madrid boss Jose Mourinho, but he faces competition from Premiership giants United and Arsenal.
Meireles is ready to leave Porto this summer and knows all three European giants are keen on him.
The midfielder's buyout clause is set at £25 million, though he could leave for £10 million.
United and Arsenal are ahead of Real for Meireles, with Mourinho's signing priority remaining Inter Milan fullback Douglas Maicon.
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