Eric Dier's former manager believes the Tottenham star's future lies in midfield and says the 22-year-old is like "very few" other midfielders in world football.
Dier joined Spurs from Sporting Lisbon in summer 2014 as an England under-21 international defender and spent last season rotating between right-back and centre-half.
This term, he has moved into a defensive midfield role, establishing himself as a key player in Tottenham's surprise Premier League title push. He has missed just one league match so far, through suspension.
The 22-year-old made his full England debut last year and he impressed in Saturday's 3-2 win over Germany, playing 90 minutes in midfield and scoring the visitors' winner with a towering header in stoppage time.
His overall display against the world champions in Berlin has boosted his chances of being Roy Hodgson's starting holding midfielder at Euro 2016, although Leicester's Danny Drinkwater will reportedly be given a chance to impress in Tuesday's friendly against Netherlands.
Veteran coach Jesualdo Ferreira, who managed Dier at Sporting in 2013, is not surprised by the success of his former charge, telling Portuguese daily A Bola: "No, not at all! When I arrived at Sporting Eric was, of all Sporting's young players, the one with the best potential, the one who had most conditions to become a top player.
"And it looks like I wasn't wrong. At the time he was too young, but on the pitch he behaved like an adult. He's a good person, with good character, and he's shy."
Dier has repeatedly refused to be drawn on his favoured position but there has been speculation that he could eventually return to the heart of defence.
Ferreira, now in charge of Qatari club Al Sadd, believes his future is as a "defensive midfielder," however.
"Curiously, many laughed when I said that, but now... I've bet on him for this position for the first time in a game against FC Porto and he corresponded. He gets to the box well, heads well and shoots well," the 69-year-old added.
"Curiously, Eric isn't the typical English player. He's a midfielder like very few in current football.
"I'm very impressed with him and he has justified my confidence. Drinkwater also plays in Dier's position and there is still [Jack] Wilshere, who is injured. If the three are available for the Euros, it will be a good headache."