The Portuguese winger has the whole of Spain speculating as to why he 'feels sad', writes Andy Mitten
Melancholy in Madrid for Cristiano Ronaldo
The 27 year old is at the peak of his power and has scored an astonishing 150 goals in 150 appearances since moving to Spain three years ago.
Such has been his success, nobody questions the €96 million (Dh442.5m) world record fee for the player as they have with fellow 2009 arrival Kaka.
The club legend Alfredo di Stefano described him in a leading newspaper as a "player without limits" a month ago. Madrid loves Ronaldo and Ronaldo appeared to love them back.
Although not club captain, he led his side to the Spanish title in May, breaking Barcelona's run of three successive triumphs.
Ronaldo showed he was up to the challenge of usurping Lionel Messi by scoring the winner in a crucial league game at Camp Nou.
Ronaldo's private life is settled, he is a father who enjoys Madrid, where his Russian supermodel girlfriend often visits.
Rich, good looking, talented and famous, life appeared perfect, but then "the human heart likes a little disorder in its geometry", according to Louis de Berniers in Captain Corelli's Mandolin.
Ronaldo certainly caused disorder when he told journalists that he was "sad" after Sunday's victory over Granada.
He refused to elaborate further, leaving Spain to speculate at why he could be sad.
Was he angered that Andres Iniesta had been named Uefa's Player of the Year a few days earlier in Monaco? Had his relationship with several key Real teammates soured? Did he feel undervalued by his club? Was he just after a pay rise to reflect his status as the first or second best footballer in the world?
At present, lesser stars such as Samuel Eto'o, Wayne Rooney and Zlatan Ibrahimovic all receive larger salaries than Ronaldo, who will also see a further decline in his remuneration following a change in the Spanish tax laws.
Factor in also that Real are a club like no other. The atmosphere is more intense, more political, with shifting plates of power behind the scenes and a huge media influence.
At Manchester United, Ronaldo was encouraged to concentrate on football and nothing else.
United's ownership structure is unpopular with fans, but Sir Alex Ferguson shields his players from the politics.
United's media were regularly encouraged to produce articles praising him to show that he was appreciated.
Does he really not feel that in Madrid, or is it actually just about money?