Bale must meet huge expectations after signing from Tottenham for a world record €100 million.
"No footballer is worth paying that amount of money for. There is a lot of pressure on him," Ibrahimovic told BBC Sport.
"I know that when Zidane played for Madrid, the fans were whistling against him. If they can whistle against Zidane, for me one of the best players in history, I hope Bale has a lot of patience.
"I had a dream to come to Barcelona, but afterwards I am thinking that maybe you should keep your dreams, instead of making it come true.
"Bale's move is similar to my transfer to Barcelona, but what creates that situation and the fee is the media, the selling club and how desperate the buying club are to buy a big name."
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