The 19-year-old defender was educated at the famed Portuguese club and broke into their first team during the 2017/18 season, before a move to Old Trafford was completed during the summer.
"Jose was a big influence on me coming here,"
Dalot explains. "
He was very important. His history speaks for itself, the way he is coaching and the way that he has made football change.
"It is the fact that is he is Portuguese too. The relationship that he has with the players is very good, and it was quite impressive to me. He pushed me to come here and the way that he believed in me was very good. That is why I am here. He is a big reason why I came."
Mourinho is of course a former manager of Porto and remains their most successful boss in history, after guiding them to the Europa League, UEFA Champions League and multiple championships.
Dalot believes that unique knowledge of the club was key to him being head-hunted in the summer.
"It is a big connection with Porto,"
says Diogo. "
He knows the former club where I played. He knows the way I think because players in Porto think in a different way to the other clubs and he knew that.
"So he was very, very important to me. I don't have doubts that in Portugal, the best club to form a player is Porto. It was a very good 10 years to develop, not just as a player but as a man. But it was important to make this step. The coach helped me to do it and it is a lot easier with him here."
Cristiano Ronaldo is another important connection between United and Portugal, which was also an influence when Dalot was making up his mind in the summer. The youngster describes as our former no.7 as the best player in his country’s history and is continually inspired by his famous work ethic.
"Cristiano, I don't need to describe him because you already know him. For me, since I remember, he was the inspiration to play football and of course, if you asked me if the fact he played here was also an influence to come, then of course I say yes. The way he played here, the way he developed, was unbelievable. I want to make that step too, to improve and play for many, many years here.
"He is an inspiration for everyone, for every player, for every young player. To have a player like that in the world, we just have to enjoy it for as long as he stays with us, playing and giving us the opportunity to enjoy his football. It was a proud few years for Manchester to have him here and, hopefully, one day the United fans will say it was good for them to have Dalot here."
Amusingly, Dalot was not always a fan of Ronaldo – specifically, when United beat Porto in the 2009 UEFA Champions League quarter-final second leg, thanks to a rocket-fuelled strike from Cristiano.
"I was in the stand, right behind the goal that he scored,"
Diogo recalls. "
Of course at the end I didn't like it because I was - and still - supporting Porto. We played good, but playing against this team was always difficult and especially when you have Ronaldo. It was an impressive goal.
"I had not seen a goal like that before. It was my first live match seeing Manchester, so seeing that goal was impressive. I was not happy at all, but when you like football and goals like that then you need to recognise it."
Source: Manchester United FC / Mark Froggatt