Widespread reports in recent days have suggested the Portuguese superstar is ready to call time on his Bernabeu career.
Tax fraud allegations made against him, which he strongly denies, have pushed him to wanting to leave the Spanish capital.
But according to the Mirror, Ronaldo has been keen for a fresh start elsewhere for some time and even told his former boss, Ferguson, of his unhappiness.
The duo have remained close ever since his £80m move from United to Madrid in 2009.
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And at a function they both attended several weeks before the Champions League final, Ronaldo is said to have confided in Ferguson about feeling unloved at the Bernabeu.
He feels let down by some of the supporters who have booed him over the season – despite him firing them to La Liga and Champions League glory last term.
He also isn’t a fan of the dressing room atmosphere and misses the camaraderie he had at United, that is nothing like he has endured at Madrid.
The report adds Ferguson would love to see him back at Old Trafford.
The Scot still has an influence within United’s hierarchy but it remains to be seen whether he can convince Jose Mourinho into making a move for him.
Ronaldo and Mourinho shared an up and down relationship during their brief spell together at Madrid and the former Chelsea boss could be prioritising other targets.
Alvaro Morata, Ronaldo’s team-mate, Inter Milan’s Ivan Perisic and Everton forward Romelu Lukaku are all said to be on his wishlist.
Source : EXPRESS