The Portugal international has now scored in 15 different club competitions with four different teams.
Sarri is excited with the current form of Ronaldo, who took his 2020 tally to seven goals in just four games.
"Ronaldo is in extraordinary physical and mental condition," the former Chelsea head coach said.
"He is continuing at an impressive pace and has extraordinary skills.”
"He is very well physically. In terms of explosiveness, he is good. He takes great care of the details.”
"Ronaldo is a champion, we want to help him win the sixth Ballon d'Or, it would make us all happy."
Juventus have now won five consecutive matches in all competitions, and have built a four-point lead over Inter Milan.
Despite the Bianconeri’s impressive form in 2020, Sarri said the Serie A champions must work even harder if they are to retain their title.
"Winning is becoming normal," the 61-year-old added.
"I'm happy for the team, but we don't have to look at the numbers because it will be more difficult this year.”
“We will certainly have to do better than previous years if we want to be competitive in the league.
