Peterborough United have signed Portuguese defender Ricardo Santos on a three-and-a-half-year contract.
Santos has arrived on a free transfer from Thurrock, having played 24 times this term in Ryman League North.
A former Dagenham & Redbridge youth player, the 18-year-old, 6ft 5ins centre-half started the campaign with Dover Athletic.
"He is one for the future, but one that we know a lot of clubs were looking at," said Posh boss Darren Ferguson.
"Potentially, we feel he is a good signing for the football club."