Real Madrid's 65 million euros signing Kaka explained this Tuesday why he has been playing at below his best.

Kaka was substituted in the second half of his side's Champions League exit against Olympic Lyon a week ago after another disappointing display.

Speaking in a televised interview with Diario AS on Tuesday, the Brazilian, who joined from AC Milan last summer, explained that the groin problem that had kept him out of action for two months at the end of 2009, had been a major factor in his poor form.

"I have problems with my pelvis when I arrived from Milan and that slowed me down," he explained.

"I also needed time to adapt to living in the city of Madrid, the club and other things. The injury slowed the adaptation down and things like that take away your confidence and you can't do things you are used to doing," he added.

However, Kaka moved to distance himself from comments made by his Press Secretary Diego Kotscho on the Twitter social networking site.

Kotscho called Madrid coach Manuel Pellegrini a "coward" for his decision to substitute Kaka in the game and added he had only done it to pass the blame for the defeat to the player.

"When Diego put the message out I was on the pitch, so I had nothing to do with it", explained Kaka.

"Diego is my press secretary, but he has his own opinion like has any other fan. I made it clear that was his opinion and I did not agree with it," he said.