Maicon's agent claims Manchester City and Real Madrid are now showing an interest in the Inter Milan full-back.
Chelsea had been strongly linked with a bid for the Brazilian after Inter president Massimo Moratti suggested it would be '50-50' whether Maicon stayed at the San Siro.
However, big-spending duo Real and City are now ready to enter the chase, according to the player's representative Antonio Caliendo.
Real were not previously thought to be considering a bid for Maicon, but Caliendo is now waiting to see if Moratti accepts any offers.
"Maicon is the best right-back in the world," Caliendo told Antenna 3.
"Real are interested and I think Manchester City too, but not United.
"However, it is up to Massimo Moratti to decide. I would be happy if Maicon stayed here to try and win the Champions League."
Regarding Moratti's comments that it is possible Maicon could be sold this summer, Caliendo concedes a move can not be ruled out.
He added: "If Moratti said that then it's right. He is in charge and he knows better than anyone else.
"This is football nowadays, things change very rapidly. Everybody can be sold or bought.
"For all I know Maicon is tied to Inter for the next four years. He is a serious professional and not a party animal like they describe him in Spain."