BBC Sport revealed in July that the Blues were monitoring Robinho, although media reports that they had made a £48m bid were wide of the mark.
Chelsea confirmed on Thursday that they have made a formal offer for the former Santos star.
"We know that Chelsea are interested in signing him," Calderon added.
"I don't mind that other clubs try to sign our players - it's normal, we have very good players. Anyone would like to have one of them for sale.
"But Robinho wants to be with us. He is one of the best players we have in our team and we need him for next season."
Chelsea chief executive Peter Kenyon said on 3 August that, although talks with Real had stalled, he remains hopeful that a deal for Robinho would go through.
Kenyon believes Madrid's eagerness to secure a replacement is the only factor preventing him from moving to Stamford Bridge.
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"A key issue over buying Robinho has always been that Real are looking for a replacement," he told his club's website.
"It is fair to say that is what has been holding up discussions."
Scolari, who took over as Chelsea boss in July, is currently working on bringing in new faces ahead of his first Premier League campaign.
Robinho has previously stated: "It would be a dream for me to work with Luiz Felipe Scolari, who is one of the best coaches in the world.
"I have always spoken highly of him and he has always spoken very highly of me, since well before he was at Chelsea.
"In 2003, when I was unknown in Europe, he called me to play in a charity match. It was brief but it was enough for me to see his style and character."
And Robinho's agent, Wagner Ribeiro, was reported as saying in Spain: "Madrid have failed to value him as he deserves and I do not like the fact that they tried to include him in the Ronaldo deal. Money is not the problem for us now.
"What matters for Robinho is to leave the club and play for Scolari at Chelsea."
Ribeiro also told Spanish newspaper Marca from Bogota, where Real are currently on
tour: "Robinho is very angry with the way the Madrid bosses are dealing with him.
"He calls me every day to know whether anyone has spoken to me about his future, and I always have to tell him that no one has called.
"I have been trying to speak with someone from the club for three days. Robinho does not understand what is going on."