The Colombia international has shone for Bayern in his first season with the German giants.
Diaz told Sky Deutschland: "When FC Bayern approached me, it was clear from the very first moment that I wanted to go through with this transfer. It filled me with pride because I had known the club for a long time and basically understood what to expect there.
“It was a good decision – a decision for an incredible and outstanding team. And when you arrive somewhere new, you naturally want to give your very best, to give 100 per cent and to feel comfortable where you are. Being happy is the most important thing for a player and for his family as well. It was exactly the right move to come here.
“I knew I would be joining an incredibly strong group of footballers and a club with excellent infrastructure and top-class training facilities. I had no doubts about that. The most difficult part for me and my family certainly was and still is the language…
"But I knew I would fit in very well here and that I would contribute my part to the team’s success – just as I did previously in Liverpool. FC Bayern placed their trust in me, and I am trying to repay that trust on the pitch."