It is a common maxim that money cannot buy you happiness and Cristiano Ronaldo, one of the world's best paid players, appears to have become the latest to acknowledge this after saying he was "sad" at Real Madrid.

The Portugal forward, who cost Real a record 94 million euros ($118.49 million) in 2009 and who earns around 11 million euros a year, refused to elaborate after Sunday's La Liga win but added that it was for professional not personal reasons.

"The people who work here know why," he said after their routine 3-0 home win over Granada in which he scored a brace, and his comments dominated the sports headlines in Spain on Monday.

"Enough is enough" ran the front page of sports daily Marca over a photo of a serious looking Ronaldo.

"CR7 unsettles Madrid and activates the alarm bells after failing to celebrate his goals against Granada."

An El Mundo comment piece was headlined "Rich, good-looking and sad."

Radio station Cadena Ser and other media reported that Ronaldo had held a meeting with Real president Florentino Perez on Saturday where he said he did not feel he had the support of the dressing room, he was unhappy and wanted to leave.

Ronaldo himself dismissed the idea that his feelings had anything to do with losing out to Andres Iniesta for the Best Player in Europe award on Thursday.

There was speculation in some media that he was unhappy that he had not been offered an improved contract after his goal-scoring feats over the last three seasons.

"Cristiano has the right to be annoyed about whatever he seems fit," wrote a columnist in sports daily AS.

"But it shows a lack of respect to his colleagues and the fans to be angry for reasons that one is not brave enough to make clear. If he wants more money, come out and say so."

Ronaldo, who netted 46 league goals last season, has had a relatively quiet start to the campaign and looked below par in Real's league opening draw against Valencia and in their shock 2-1 defeat at Getafe.

The 27-year-old scored the winner against Barcelona in their Spanish Super Cup second leg win on Wednesday, but was pointedly serious and downbeat after scoring his goals against Granada on Sunday.

Ronaldo, who asked to be substituted with a knock to his left thigh in the second half, joins up with the Portugal squad on Monday for their World Cup 2014 qualifiers against Luxembourg and Azerbaijan.

- Reuters