The Red Devils have been linked with a move for the Portugal international on a number of occasions over the past two seasons, although a big-money transfer has failed to materialise.
The 30-year-old has become Real Madrid’s record goal-scorer after netting 325 times in 311 appearances for Los Blancos since his £80m move to the Spanish capital from United in 2009.
Former Red Devils centre-half Ferdinand poured cold water on talk of Ronaldo returning to United unless Louis van Gaal’s side are competing for the Champions League on a regular basis.
“The biggest thing about it is that he is competing to win the league and Champions League every year,” Ferdinand told BreatheSport.
“The Champions League is his holy grail. Does he seem himself doing that at Man Utd immediately? He doesn’t have time to waste. He hasn’t got time for a transitional period. So that ends the conversation.”
United are in second place in Champions League Group F after a 1-1 draw with CSKA Moscow on Wednesday night.
Ronaldo has won La Liga, the Champions League and two Copa del Rey trophies during a six-year stay at The Bernabeu.
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