Manchester United ace Cristiano Ronaldo says he wasn't surprised by Manchester City's £100 million bid for AC Milan star Kaka.

"Special players are maybe worth that," said Ronaldo. "I agree with that. When you are good, when you are a special player, you are more expensive than the other ones. That's normal.

"It's like cars. Some cars are better than others, that's why they're more expensive. It's the same with players. But this is only my opinion."