Manchester United striker Cristiano Ronaldo has thanked Iker Casillas for his support ahead of the World Cup.

Casillas warned critics of his former Real Madrid teammate not to underestimate Ronaldo's ability to still dominate for Portugal in Qatar.

Ronaldo said today: "Iker is a person with whom I have a great relationship, we have won many things together.

"I understand what is going on. Nothing surprises me. I agree with him and hope to demonstrate that we are eliminating that small range of criticism.

"There's millions of people who like me. That is my motivation. There is no money to pay for that."