Real Madrid's Brazil striker Ronaldo insists he is preparing for surgery on a knee injury that hindered his performances in the World Cup finals in Germany.

Ronaldo managed to score three goals and become the leading scorer in finals history, but failed to find top gear and says he needs an operation to cure the problem.

"It is better that they operate on the calcifications thereby removing the problems they have caused me over the past eight months," Ronaldo told El Mundo.

"I will travel to Brazil shortly to see if I will finally have surgery to sort out this minor problem.

"I won't be out for very long because it is not a serious operation and I think the benefits will be greater than if they don't operate.

"Either way I will be ready to start the season with Real."

An earlier statement on Real's official website had stated: "Ronaldo returned from the World Cup with pain in his left knee that obliged him to be examined by Real's doctors.

"The player has now been told to rest to preserve the tendon in his right knee. For the moment surgery has been ruled out."