The 22-year-old Frenchman signed for Borussia Dortmund in July 2017. As of June 2021, the defender has made 73 appearances for BVB, scoring four goals and providing one assist. He was part of the side that won the DFB-Pokal in 2021.

Zagadou was born in 1999 in the Parisian suburb of Créteil. He made his first steps in the game of football playing for local clubs before being scouted by the Paris Saint-Germain youth set-up in 2011. He worked his way up through the age groups before breaking into the reserve team, making nine appearances in the French fourth-tier in the 2016/17 season. In the summer of 2017, the 18-year-old moved to Dortmund, reportedly turning down the advances of both Manchester City and RB Leipzig in favour of BVB. ''Signing for Dortmund was unquestionably the best decision for me,'' says Zagadou, going on to add: ''Everything I had hoped for has come true. I consciously chose to sign for BVB because they have a strong track record of bringing young players into the first team and helping them develop at the highest level.''

In his first season at Borussia - 2017/18 - Zagadou was often deployed at left-back to cover for injuries to the regular starting personnel. A year later, he was able to secure a starting berth in his favoured role at the heart of defence. However, a series of injuries led to him missing large chunks of the second half of the season. The youngster had certainly made a good impression before being struck by this ill-fortune. In total, Zagadou won 70% of his duels (75% in the air) across the season – the second best record in the entire league! BVB kept a clean sheet in six of the 17 league matches in which Zagadou played – something they only managed to do four times in the 17 matches without him. In November 2018, the broadsheet newspaper Frankfurter Allgemeine Zeitung singled out Zagadou as a ''key figure in BVB's success.'' Former head coach Lucien Favre was equally effusive in his praise: ''Dan is able to read the game very well. He's made so much progress. It's incredible.'' With the switch to a three-at-the-back formation in the 2019/20 season, Favre once again called on the services of Zagadou whenever he was fit. Injuries meant the 1.96-metres tall centre-back made just nine league appearances in the 2020/21 season. He had to undergo a further knee operation in March 2021.

In addition to his imposing physique (he weighs in at 90kg), what stands out most about Zagadou is his incredible sense of calm on the pitch. In many ways, he's not too dissimilar to former Brazil goalkeeper Júlio César, whose pulse reportedly never surpassed its resting level in even the most high-pressure situations. When Sebastian Kehl, director of professional football at BVB, pours forth with praise for Zagadou, one might expect that it would be because of his physical presence or his strength in the tackle. However, Kehl is every bit as impressed with his ''ability to remain calm in difficult situations.'' Sporting director Michael Zorc has deemed this quality ''a special gift.''

As Zagadou has made the move into an unfamiliar part of the world, his family have been there to help him every step of the way. His parents accompanied him on the journey to Dortmund, while his siblings have done all they can to make sure that he feels at home in his new city. Dressy, the eldest of his four brothers, has gone as far as to move in with him in Dortmund. For Zagadou, this arrangement clearly gives him an important sense of security: ''My elder siblings have always kept a close eye on me. They've always made sure I don't end up in trouble.''The capacity to remain so well-balanced at such a young age is undoubtedly one of the most striking features of the young defender whose teammates call him Daxo. The Frenchman believes it all stems from the environment in which he grew up. ''Back there, there's no point getting too worked up about things. Keeping it cool is the best approach.'' That being said, Zagadou confesses that in certain exceptional circumstances – and only then – he sometimes loses his cool: ''But only when the opposition show no respect or sense of fair play. Fortunately I have Axel Witsel to hold me back in those situations,'' says Zagadou with a laugh. On the subject of Witsel: the young Frenchman feels particularly connected to the Belgian midfielder 11 years his senior. In fact, he even calls him ''tonton'' – French for uncle.