If you haven't already heard, Cristiano Ronaldo has dropped this summer's biggest bombshell by reportedly deciding he wants to leave Real Madrid.Recent allegations of tax fraud are said to be the reason behind the Portuguese's decision, having been accused of dodging €14.7 million in unpaid taxes.He now wants out of Spain as a result, sparking speculation of a long-awaited return to Manchester United.It's been eight years since Ronaldo joined Los Blancos for a then world-record fee of £80 million, during which time he's won two La Liga titles and the Champions League three times.Should the 32-year-old depart the Bernabeu this summer in what would be another world-record move, he will do so knowing he's achieved everything he possibly could in Madrid.The odds of Ronaldo rejoining United have been slashed to 9/4 on Sky Bet, while Paris Saint-Germain are second at 5/1 and 'Any Chinese Club' at 20/1.Ronaldo staying at Real remains the most likely according to bookmakers at 1/3, but that's looking increasingly doubtful.Jose Mourinho would inevitably snap at the chance to bring Ronaldo back to the Theatre of Dreams, even if he would cost over £100 million and command wages of £400,000-per-week.United fans certainly want it to happen and it would seem even a few club legends are excited by the prospect of arguably their greatest ever player returning.Rio Ferdinand has now reacted to reports that Ronaldo wants to leave Real and it's very clear how he feels about the situation.In the tweet below, the former centre-back said: "Viva Ronaldo...... 👀 @Cristiano," which, of course, translates to: "Long live Ronaldo."

FERDINAND'S TWEET

The eyes speak a thousand words. Ferdinand played alongside Ronaldo for six years at United and recently explained how he was always destined for greatness.

"He was very young, he was very inexperienced, very immature in the way he played, a bit of a show pony at times," he said on BT Sport in May.

"But he had the mentality - he had the desire, the work ethic.

"He always wanted to be a superstar but the difference is he worked beyond anyone to become a superstar, and that's what sets him apart."