Adalberto Machado, the father of Rodrigo who also serves as his son's agent, told Radio Renascenca on Wednesday that a return to the Santiago Bernabeu for the 20-year-old cannot be ruled out.
He was speaking after a report in AS mooted that the nine-time European champions were ready to stump up the 12 million Euros required to snag the Brazilian-born forward.
"Rodrigo is a player of Benfica and he has three more years on his contract," said Machado.
"If there is an interest from Madrid, it is because he is doing a good work and that is always a reason to be satisfied.
"Madrid had secured a buy-back clause, but it no longer exists, so if they want him again then they will have to negotiate with Benfica,".
"Rodrigo is very satisfied at Benfica. He is still getting settled and has experienced players like [Oscar] Cardozo and [Javier] Saviola still ahead of him, but he is having a good amount of playing opportunities."
Madrid swooped for Rodrigo in 2009 after he departed from Celta Vigo but the striker was offloaded to Portugal after plying just one season with the club's B and C outfits.
Rodrigo, who impressed in a loan spell with Bolton Wanderers last season, donned the national colours of Spain in the Under-20 World Cup during the summer.
He has played seven times for the Portuguese giants in the Primeira Liga this campaign, having already notched three goals.