https://www.football-italia.net/146311/sarri-juve-thank-ronaldo
Sarri Confirms hes had a knee probem for last month hurt the ligaments.
“We must thank Ronaldo, because he made a sacrifice to be there at all tonight in a difficult situation. He did everything possible to play, but I saw he was not well and thought it best to take him off,” Sarri told Sky Sport Italia.
“It’s only natural a player is going to be irritated to leave the pitch, especially when he worked so hard to be there. Over the last month, he has had this little knee problem, he had a knock in training and it hurt the collateral ligament. When he trains at high intensity or plays, it unbalances him, so he ends up overcompensating and it damages the calf and thigh muscles.
“It is affecting his performances and he is not at his best at the moment. All players who are trying to give their best will have at least five minutes of being annoyed when they are substituted, but a coach would in general be much more worried if he didn’t seem upset.”