The pair worked together when Guardiola was in charge of Bayern.
Alaba told Four Four Two: “First of all, he meant a lot to me. He took me to another level.
“Under him, I knew I could play a lot of positions. He is one of the best coaches in the world, if not maybe the best from what I have seen.
“He bought a new style, not only in our team. We learned a lot about football and the style we played was great.
“We didn't win the Champions League but we were very unlucky in that period. But the style we played was great."