Eric Dier has dreamed the dream for as long as he can remember. For the tall and composed defender, it has always been England and the Premier League, and now the 20-year-old is poised to turn it into reality with a £4m transfer to Tottenham Hotspur.

What makes Dier a rarity is that he is a product not of his native England but Portugal, to where he emigrated with his family at the age of seven after his mother, Louise, who works in the catering industry, got a job in the country before the 2004 European Championship.

Dier’s journey has taken him through the renowned Sporting Lisbon academy – which has graduates such as Luis Figo, Cristiano Ronaldo and Nani – to a professional contact at the club in April 2010, on into the B team and then the first team. He is now on the verge of what amounts to a homecoming.

Dier, who was born in Cheltenham and lived in Sussex before the move to Portugal, has been tracked by Tottenham and other English clubs for several years. Sporting had to withstand competition from Manchester United – the club Dier supported as a boy – Arsenal and Tottenham for his signature on that first contract in 2010 while he also had six months on loan at Everton’s academy in 2011.

Tottenham have made their move, with Mauricio Pochettino believing that Dier could not only provide competition in central defence but cover at right-back and in defensive midfield.

Dier stands to follow the goalkeeper Michel Vorm and the left-back Ben Davies, who both joined Spurs from Swansea City, while Pochettino remains confident about prising the midfielder Morgan Schneiderlin from Southampton, despite his former club’s resistance to the proposed deal.

“Ultimately, I want to test myself against the best and the Premier League is where I dream about playing,” Dier has said, in the past. He has represented England at under-18, -19, -20 and -21 levels. “I think it is the dream of any kid to play for England and play for your country,” he has also said.

Dier commands fascination and respect in England because of the career path he has taken. In an era when so few English players appear willing to broaden their cultural and linguistic horizons with moves to mainland Europe or further afield, he stands out.

Dier was recommended to Sporting as an eight-year-old by the PE teacher at his English-speaking school and, having impressed, he trained with them at their facility in central Lisbon until he was 13. At 14, he moved to the club’s academy and, also, to a Portuguese school, where he had no choice but to immerse himself in the language.

Completely fluent, and at ease with the Portuguese lifestyle, Dier set himself the target of making the grade at Sporting. He had offers to return to England – and there was the spell at Everton – but he reasoned that the opportunities would be greater at Sporting because of their hard-earned reputation for bringing through young talent. He knew that players can get lost in the academy systems at the big English clubs.

Dier stayed in Lisbon even after his family went back to England in 2010 and the breakthrough came in 2012-13, when he made 15 appearances for Sporting’s first-team and was feted for his performances. He made a further 15 appearances for them last season.

He is 6ft 3in and, in addition to his physicality and threat at set pieces, he brings comfort on the ball, technique and an ability to read the game. He chimes with the sort of football that Pochettino is seeking to play at Tottenham, while he appears mature beyond his years.

Dier is of sporting lineage. His maternal grandfather is Ted Croker, the former FA secretary, who played for Charlton and Kidderminster, while his father, Jeremy, was a professional tennis player.

In September 2010, he was chosen by Umbro as one of the faces of England’s future and he featured in an advertising campaign alongside Wayne Rooney, Joe Hart, Jack Wilshere and Theo Walcott. His visibility is set to become broader.