Thomas Tuchel believes Kevin De Bruyne leaving Chelsea back in 2014 could have been the best decision for him, but the club 'will never know' if it was a mistake.
De Bruyne was sold to Wolfsburg in 2014 for a fee worth a reported €20 million, after just five league starts for the Blues.
He was a peripheral figure in Jose Mourinho's squad and was eventually sold to gain regular game time. The Belgian flourished in Germany before heading back to the Premier League to join Manchester City 18 months later.
Now he is on the verge of winning another league title. City can achieve their third title in four seasons with a win over Tuchel's side at the Etihad and the Chelsea boss has reflected on his departed over seven years, making comparisons to Timo Werner and Kai Havertz's situations at the club.
What Thomas Tuchel said on Chelsea selling De Bruyne in 2014
"I don't know; I wasn't there," said Tuchel on if Chelsea made a mistake letting De Bruyne leave, as relayed by Goal. "I can just say that you can get caught up in the thoughts that it was a big mistake to let him go, but you never know. You don't know what would have happened if he would not have changed the club back to Germany from Chelsea and then back to England after that.
"Maybe he needed it at the time. A different league, a different challenge to be at his best level that he has maybe ever reached to be so influential at City and even be the captain for an amazing and such a successful team.
"You don't know; maybe it was for the best for him. Maybe he would have done the same route had he stayed and forced his way in here. It is hard to tell, hard to tell but what I can tell you is that this league here, because you draw a comparison to Timo and Kai's situation, the league here makes you either do it or don't do it.
"This league is the best here to challenge every player and coach at the highest level in football. You have two possibilities, you step up or you don't. If you don't, you don't make it in this league and that's why I am very happy that Timo and Kai both stepped out of their comfort zone and took this adventure, this huge challenge, come to England, go abroad in the hardest league and go to a club with a real winning mentality.
"A tough club that's not about second or third place; this is about winning. This is bravery and it is the right step for them to bring out their very best. This is very good because it is the league and challenge that demands it and sharpens their character.
"It's their mentality and this is what we can see. They are still on their way, we will boost them and this is always a process. For some, it is faster and for others, it is slower, but as long as they are all Chelsea's players, they get our full support."