There is growing speculation that Premier League rivals United are weighing up a move for England international Dier, with Jose Mourinho determined to reinforce his midfield stocks.
And Pochettino seemingly made an attempt to ward off any interest in the 23-year-old, who can play in defence and midfield.
"Analyse Eric Dier, from where he came," Pochettino said ahead of Saturday's trip to Burnley. "He came from Portugal, but I think people are a bit confused sometimes. Before, he was in Everton and then he went to Portugal with Sporting, and we signed him as a player with potential.
"We provided all the tools to be a Premier League player. My first game in charge against West Ham, he started as a centre back, next to [Younes] Kaboul. Kyle Naughton got a red card, he moved to full-back and scored.
"That season, he played like a full back, like a centre back but never as a midfielder. Then in the summer, we were looking for a midfielder and we had plenty of options [to buy one], but I decided to play Eric in midfield.
"I created a system that he felt comfortable in. He played like a midfielder without the ball, but with the ball he was a third centre back. You can see in possession he dropped in between the centre backs or between the full back and the centre back, and always we play with three.
"People say now Chelsea changed the system, but no we played always the three in possession. Out of possession, Eric moved in front and without the ball he tried to press and play like a midfielder.
"Then we signed Wanyama and played both, but we had some injuries like Toby [Alderweireld] and Jan [Vertonghen], and Eric was the perfect player to play as a centre back. That is a good thing for the player, the possibility to play in different positions and do well in every one."