Madrid are poised for a huge summer under the Frenchman after a hugely disappointing campaign domestically and in Europe.
According to one of their former managers, Zidane will have a significant budget to fund a rebuild at the Bernabeu.
According to Capello, Zidane’s transfer pot could be as large as €500 million (£430m).
"I was in Barcelona and I was told that this year Real Madrid have €500m to spend," Capello told Sky Sports Italia.
"I asked, 'Are you sure?' The answer was yes and that came from someone who knows a lot about Real Madrid."
Los Blancos have endured a miserable 2018/19, crashing out of the Champions League at the quarter-final stage and trailing Barcelona by 13 points in La Liga with six matches to play.
A raid on Premier League clubs could be high on the Frenchman’s agenda, having been linked with the likes of Eden Hazard, Paul Pogba and Sadio Mané in recent weeks.
With a number of new Galacticos expected to arrive, there could be some big names on their way out too; Gareth Bale, Isco and Marco Asensio have all been linked with moves away from Spain.
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