England under-21 defender Eric Dier has completed his move from Sporting Lisbon to Tottenham Hotspur, the Premier League club have confirmed.
Spurs are believed to have paid four million pounds for Dier, 20, who was born in England but moved to Portugal as a child.
The defender progressed through Sporting's academy to the first-team, making his debut in 2012 and since then racking up 30 appearances for the club.
Dier, who has previously spent a short time on loan at Everton, has been highly regarded in England for some time, representing his country at every level from U18s to U21s in the past three years.
He becomes Tottenham's third summer signing following the arrivals of Ben Davies and Michel Vorm from Swansea.