The England international agreed a four-year contract with Tottenham in July, ending speculation that he could leave the club after a six-year spell in north London.
Formerly a holding midfielder, he has featured prominently in the heart of defence since Mourinho replaced Mauricio Pochettino in November.
And the 26-year-old is grateful to have been given an opportunity to test himself in the position he believes gets the most out of his abilities.
“I had a health issue at the beginning of last season that I kept private and I had to have a little surgery, so I missed pre-season, so that obviously had a huge impact,” he told GQ.
“I spoke to Pochettino then, as for many years we had spoken about me playing as a centre-back, and that was where I was going to gradually move to.
“We had a really great conversation: I said, ‘I think it’s my best position, I think I can develop into something very, very good there. But it has to be now, otherwise I think I have to find another solution.’
— Eric Dier (@ericdier) September 2, 2020
“We talked for about two hours and he was really happy that I’d come to him and I had made that decision in my own mind.
“And he said, ‘okay, you’ve missed pre-season, so you’ll have one now, don’t worry if you’re not playing for a couple of months, we’ll get you physically in the right place.’
“So I was completely calm about the situation. And the last couple of games before he left, I played at centre-back.
“And so when the new manager came in I started that dialogue again with Mourinho and for me that was the biggest part of wanting to stay at Tottenham and sign the new deal – it was purely footballing.
“I was really happy that Mourinho would give me the opportunity to play centre-back again and to prove myself there. I’m really excited.”
Mourinho was appointed by chairman Daniel Levy with the intention of winning silverware and Dier, an EFL Cup and Champions League runner-up during his time at Spurs, is confident about his side’s prospects this season.
“There’s no doubt in my mind that with Mourinho, in every competition we play, he’s gonna be playing to win it, you know? And that’s all you can ask for really,” he said.
“We are extremely motivated to right a lot of wrongs from last season. We start with a clean slate with the manager, zero points and all the competitions and we start afresh.
“So I think there’s lots of things to be excited about. And a lot of work needs to go into now getting us in the right place to try and be competitive on every front.
Sporting CP academy product Dier was seen holding talks with Mourinho in Portuguese during an episode of Amazon Prime documentary ‘All or Nothing’.
However, despite the documentary dominating conversation over the past couple of weeks, Dier insists he has no plans to tune in anytime soon.
“I haven’t watched any of it,” he said. “I actually spoke to [basketball player] Steve Kerr a couple of days ago about it, because obviously he was in The Last Dance [the Netflix documentary about the record-breaking Chicago Bulls season].
“I said to him: ‘You know, looking back on an incredible season and winning and everything you did, that must be a lot more enjoyable than what it would be like for me!’
“I don’t really enjoy watching myself back anyway. So I don’t think I will watch it. But maybe, you know, in 20 years’ time or something, it could be nice to look back on, even though it wasn’t the season we wanted.”
Dier played the full 90 minutes of Tottenham’s 1-0 loss to Everton in their opening Premier League game of the season on Sunday.
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