West Ham are close to agreeing a deal to sign teenage defender Goncalo Cardoso from Boavista.
The 18-year-old centre back is on the verge of completing a £2.75m move to the Premier League side, which would see him become their fifth signing of the summer transfer window.
After making his professional debut in October last year, Cardoso went on to make 15 appearances for Boavista in the Portuguese top flight.
Cardoso has made 11 appearances for Portugal's U19 side, and played every minute as they reached the final of the U19 European Championships in July.
West Ham's major signings this summer have come at the other end of the pitch, with striker Sebastien Haller and attacking midfielder Pablo Fornals arriving for eye-catching fees.
Cardoso will face a major challenge to break into the starting XI, with Winston Reid, Fabian Balbuena, Angelo Ogbonna and Issa Diop all already competing for a place in Manuel Pellegrini's team.
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