Calderón indicated coach Zinedine Zidane would have preferred to have sold Bale rather than Cristiano Ronaldo, a club decision widely reported to be central to the Frenchman's shock resignation after they beat Liverpool in the Champions League final in Kiev.
"Zidane is not keen on him; it is a relationship that will come to an end," Calderón told BBC Sport.
"It seems it was his last game for Real Madrid. Zidane, last year when he left, he thought it was imperative to keep Ronaldo and to sell Bale, and they decided not to do that.
"It seems it is impossible for him to be here... because of the coach and the relationship with the fans. They think he is not committed and that is a problem.
"The best thing for him is to move. He should take the opportunity if there is one."