Flick is convinced he's working with a generational talent.
Speaking with BILD, Flick said of 18 year-old Yamal: "I don't think the players can compare. Lamine is a true genius. Especially at his age, at 18 years old, he decides the games alone. He is on the right track. Plus, he's very smart.
"But of course he is still very young at 18 years old and has to learn from others. We support you. I am convinced that he will be one of the best players the world of football has ever seen."
We want to help Marc
Flick was also asked about the situation of his fellow German and senior goalkeeper Marc-Andre ter Stegen.
He added, "Now we have a very young and talented goalkeeper like Joan Garcia, who is at a very, very high level. We all decided together that this should be the future of Barça. So it was clear to me what our approach was. If everything went well in terms of communication? I think there is a lot to improve, also on my part.
"For me it is important that Marc and the club have gotten closer to each other. And that they have sought adequate communication. For me it is important that Marc returns. He is a top-level goalkeeper and has our full support so that he can play at his highest level again. What can I promise you? No, I make no promises..."