Goncalo Cardoso is having a medical with West Ham ahead of a move from Boavista.
The 18-year old Portugal U 19 international defender is due to sign in a £2.75million deal.
A 6ft 2ins centre back, Cardoso has already played 15 first team games for Boavista after making his debut last year.
He is seen as one for the future by Manuel Pellegrini but can compete for a first team place too.
West Ham have already broken their transfer record this summer, after bringing in striker Sebastien Haller.
The Hammers eclipsed the previous record fee paid for Felipe Anderson last summer, as they bid to challenge in the Premier League this season.
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ukulele
0
great signing! Sorry but never heard of him COYI
oldesthle
0
We need defenders, mostly full-backs. It just would have been nice if they could have got players that can play straight away.
vaaaelmru
0
West Ham and Everton will be Lethal