Defender who made his professional debut in 2012 for Sporting CP. He has also played for Premier League club Tottenham Hotspur and the England national team.
He was part of Sporting CP's youth system from 2003-2012.
He played for England's under-18 national team in 2011.
He was born in Cheltenham, England to parents Jeremy and Louise Dier. He is the grandson of former secretary of the FA Ted Crocker.
Midfielder Joao Moutinho and Dier were teammates on Sporting CP's youth team.