Getty Images

Former Real Madrid president Ramon Calderon claims that Cristiano Ronaldo is "fed up" at the club, fuelling rumours that the Portuguese superstar could be on his way out of the Spanish capital.

Calderon, who was the club president for two-and-a-half years between 2006 and 2009, has insisted that the Madrid No. 7 has had enough of the current regime and particularly the current president, Florentino Perez, following the sale of key players last summer, per talkSPORT (h/t Goal.com):

My impression is he is fed up with the policy of the current president. When he came to Real Madrid with Arjen Robben he thought he would be a good colleague for him in the team but then Robben was sold. Two years ago it was Gonzalo Higuain sold and he didn't like that. Last year he thought it was a mistake to let Mesut Ozil leave and the last straw was selling Xabi Alonso and Angel Di Maria this summer.

Paul White/Associated Press

The quotes from the former Madrid chief will only serve to add credence to the notion that the former Manchester United man is unhappy at the Santiago Bernabeu. The two-time World Player of the Year could reportedly pick up a staggering £500,000 per week should he decide to move back to the Premier League, per Rob Shepherd of the Daily Mail.

Guillem Balague also weighed in on a potential return to Manchester United:

The European champions have struggled during the early parts of the campaign, losing two of their opening three La Liga games. And after Perez sanctioned the sales of Xabi Alonso and Angel Di Maria—two critical figures in Madrid's 10th European Cup triumph—the pressure is mounting on Carlo Ancelotti and his players after just a trio of clashes.

A continued stream of murmurings regarding the Portuguese's situation will do little to help matters, and it'll make for uncomfortable reading for Madridistas.

A fit and firing Ronaldo is capable of hauling this team off its knees and toward bigger and better things this season. However, an unsettled and disillusioned talisman could threaten to derail Madrid's campaign before it even gets going.

Armando Franca/Associated Press

It is worth considering that Calderon and Perez have not shared a positive past, with the former claiming the current boss didn't even want to sign Ronaldo when he took over in 2009, per ESPN FC. But it'd be peculiar for Calderon to come out and look to sour Perez's reputation on a whim, especially if you consider the former president's claims were preceded by comparable stories from myriad journalists and reports.

It's vital that Madrid move to address these festering rumours, and if there is a problem with Ronaldo, that the situation is pacified swiftly. Losing Di Maria and Alonso represented major blows to this setup, but with their mercurial forward on board, it's a double setback from which they can recover.

But with Ronaldo seemingly displeased by the antics of the Madrid hierarchy and the possibility of a transfer being backed up by increasingly tangible sources, Los Blancos could quickly find themselves without their talisman too. And if the club aren't careful, the sale of two important players could quickly set a worrying precedent.