Pumas UNAM winger Pablo Barrera required a work permit if he is to sign for West Ham United.
Hammers boss Avram Grant is very keen on the 23-year old Mexico international but needs to obtain a work permit so he can join the club.
Barrera has agreed in principle to a £3.5million deal to land at Upton Park amidst interest from Celtic, Espanyol and Everton but West Ham now face the battle of getting him the necessary paperwork to finalise the deal.
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