Brazil coach Carlos Alberto Parreira is confident Ronaldo will be fit to play in the holders' World Cup opener against Croatia.
A thigh injury forced the Real Madrid striker to sit out the final six weeks of the Primera Liga season, but he is close to being able to resume full training.
Parreira is pleased with the progress the 29-year-old has made in his recovery and hopes to be able to field him in his side's last two warm-up games to give him a chance to work on his match fitness.
"It seems that Ronaldo is better, he's been working with the ball and doing exercises of medium intensity," said the coach.
"Ronaldo has been running and he just needs to regain match fitness. His weight is perfect.
"He has to get rhythm and that's what the (friendly) games are for.
"Two games will not give you the ideal rhythm, this will happen only during the tournament. He will improve during the tournament."