Hazard has only a year left in his contract at Chelsea and is value at £130m by the club.
Real Madrid and manager Zinedine Zidane are confident of signing the Belgian for no more than £88m.
After netting twice in Wednesday’s 4-1 Europa League win over Arsenal Hazard admitted that it felt like “goodbye” to Stamford Bridge.
Calderon, who has experience of negotiating with Chelsea, noted that Real Madrid will have to up their offer to sign Hazard.
Calderon told Sky Sports, “It seems Hazard is coming and that is really good news for Real Madrid.
“I think now it is a matter of money. The player has said clearly that he wants to leave and he wants a new challenge.
“It is not fair to keep a player who has been there for seven years and who has one year left on his contract.
“Of course Chelsea are not easy negotiators. I know that quite well because in 2007 I had a long negotiation with Peter Kenyon at the time and Roman Abramovich about Arjen Robben.
“He was not playing for Chelsea but despite that they said the price was £35m.
“At that time it was a lot of money. I tried to reduce it many times and we waited until the last minute but finally we paid it.”