Sport says Flick 'dreams' of bringing Musiala to Barcelona.
Flick has worked with Musiala at both Bayern Munich and with the German national team - and is a big admirer.
The midfielder is locked in new contract talks with Bayern.
Barcelona believe they have a good chance of signing Musiala in the future, even if he extends his contract with Bayern Munich.
By selling players like Frenkie de Jong , 27, Barcelona would seek to create space for Musiala.
For his part, Musiala has stated in recent months: "FC Barcelona was my point of reference, my favourite team. I had a Messi shirt. The midfield with Xavi, Iniesta and Busquets fascinated me.
"I could watch their matches over and over again. On the back of my shirts, when I was a kid, Messi almost always appeared. I also had one with Neymar, but Messi was my hero, my favourite player."