The France legend believes that the 23-year-old, who has been linked with a move to Zidane's former club, has been on a higher level than the majority of players in the Champions League.
"This year the player who's impressed me most is not actually playing in the Champions League," Zidane told Sky Sports News. "He's playing in the other cup and that's Bale.
"He's unique. He makes things look easy, his pace is frightening, his acceleration is unbelievable because of his ability to go through the gears in very little space."
Spurs are preparing to take on Basel in the first leg of their Europa League quarter-final this Thursday.