Zidane feels the versatile midfielder, who has since developed into a key player at the Santiago Bernabeu, was the missing link at the club and hopes he will stay at Madrid for a long time.
"We signed Toni because we want him to mark an era. We absolutely love him," the former France star told Sport Bild.
"Toni is the type of player we were missing before, the missing link. He is perfect for Madrid.
"He played for Bayern for quite some time and we hope that he will stay at Madrid even longer.
"Madrid's style has changed since he has joined. We knew that he was used to German football and that the Spanish game is something else. The beauty of the game is important in Spain as well, in particular at Madrid.
"But he has adapted right away. You can hardly see that Toni is a German any more."
Kroos has played in 10 of Madrid's 11 Liga fixtures so far this season.