The television images showed Ronaldo leaving the field with a somber look and muttering a few words in the direction of the bench before going directly to the locker room to be replaced by the Argentine Paulo Dybala, who later was the author of the only goal of the match.
According to Sky, the Portuguese star left the stadium before the final whistle.
"A problem with Ronaldo? No, on the contrary," coach Juventino Maurizio Sarri replied when asked about this issue by a Sky journalist.
"First, I thank you for being available when you are not in exceptional physical condition. I preferred to change it because I didn't think it was very good. But you tried everything to be willing to play," the coach added.
"It is normal to be angry when leaving. This is valid for all players, especially for those who make sacrifices," he insisted.
Asked if he was going to admonish the Portuguese for his attitude, Sarri replied: "No, there is a threshold of tolerance with those who give everything."
"Five minutes of anger seems normal to me. A coach likes to see a furious player on his way out. Otherwise I would worry," Sarri reiterated before giving details about the fitness of the Portuguese striker.
"He has had a small problem in the knee, received a blow in training. Since then he has a little discomfort. He is at a time when he can not train to the fullest. He can not kick 100%," he concluded.