The agent of Cristiano Ronaldo has fielded interest from three heavyweights as reports break of the Real Madrid star considering his future.AS says Ronaldo is seriously weighing up quitting Real at the end of the season after becoming fed-up with the lack of public support he's received this season. The latest episode at Levante involving the elbow incident with David Navarro has left Ronaldo questioning whether Real officials are fully behind him.

Aware of developments, agent Jorge Mendes has already been contacted by Manchester City, PSG and former club Manchester United to register their interest and to ask to be kept up-to-date on the situation.

Only over the weekend, United manager Sir Alex Ferguson floated the idea of having first refusal on Ronaldo should he become available.