The 28-year-old Real Madrid forward trained with his teammates today, but he appeared to be careful not to put his full weight on his strapped knee as the squad went through some jumping drills.
Eduardo told reporters after the training session: "Cristiano is training well, he's training hard and we are sure he's going to be 100% to help us and to have an excellent game.
"He's healthy and he can't wait to start this tournament. He's determined and he wants to play to the limit, like all of us, with an immense will to win and give our best.
"You can see it in training, in the hotel, and that's certainly going to reflect in the tournament."
Ronaldo sparked fears over his knee problem when he had it iced after training on Thursday.