The left-back has seen up close Bale's emergence this year.
He told The Sun: "At the moment he is the best left midfielder in Europe. He has been that way for the last few weeks. He is young, he loves to attack and he defends to help me. I enjoy playing behind him. He doesn't take it easy.
"He likes to attack but he also helps me to defend. He's perfect for me.
"He is so good he makes me want to play better.
"I am not surprised at the reaction because if you score a hat-trick away to Inter Milan and then make two goals like he did against them two weeks later, you're going to make people sit up and take notice.
"If you saw him off the pitch, you would not say, 'There is the player who scored a hat-trick against Inter Milan'. He's very uncomplicated and very quiet."