The Barcelona centre-back has lavished praised on the former Tottenham star but believes only time will tell whether the Wales international will be worth the £86 million fee
The 24-year-old signed a six-year deal with Madrid on Sunday to complete his world-record move from Tottenham to the Liga giants and Pique has little doubt the Wales winger will succeed at his new club.
"Bale has an extraordinary left foot. I have no doubt that he will do well at Real Madrid," Pique told Onda Cero.
"He has really grown a lot in the past few years. He has developed as a player and has gained a lot of experience.
"He has joined a big team that paid a lot of money for him. Time will tell whether he's worth his transfer fee."
Bale will be officially unveiled during a press conference at the Santiago Bernabeu on Monday at 12:00BST.