Dier worked with Ferreira at Sporting in 2013, and he has underlined the influence the Portuguese boss had on him.
It was Ferreira, who won three successive Primeira Liga titles with Porto from 2007 to 2009 and the Egyptian Premier League with Zamalek in 2015, who handed the 22-year-old his first role role in defensive midfielder.
The England international, who joined Tottenham from Sporting in the summer of 2014, played as a central defender until March 2, 2013, when for the first time he was used as a defensive midfielder against Porto in a match that ended in a goalless draw.
“He had great faith in me in that position,” Dier told The Times. “That was a defining moment for me when I played in that position against Porto.”
Dier has cemented his place as the defensive midfielder in the Tottenham team, and he is also set to feature in that position for England at the Euro 2016 finals in France in the summer.
The youngster was one of the best players for Tottenham this past season and played a massive role in the North London outfit finishing in the top four of the Premier League.
The Englishman scored three goals and created 18 chances in 37 league matches for Spurs during the 2015-16 campaign.
Dier had a pass accuracy of 83% and a shot accuracy of 33%, and won 84 headers, eight dribbles and 64 tackles.