Ronaldo, 33, joined the Old Lady this summer after 10 successful seasons at Real Madrid.
The Portuguese forward scored 450 goals in 438 games in all competitions, collecting four Champions League titles near the end of his stint.
Age does not seem to have affected Ronaldo, whose physical condition remains terrific as he enters the years usually associated with retirement.
Juve midfielder Blaise Matuidi recently praised Ronaldo, saying: “He is 33-years-old, but he is really an example.
“It’s just fabulous, a real example. When I see him I understand that there are no shortcuts in football.”
Now another club team-mate, Chiellini, has predicted that Ronaldo will continue to play at an elite level until he is 40 years old.
“If we can play up to forty years, both [of us]?” he asked.
“Yes, although I do not think I will do it.”
Chiellini, 34, has amassed 692 senior appearances to Ronaldo’s 885.
But is it not just the first-in-last-out attitude sets his team-mate apart, with Chiellini revealing Ronaldo’s secrets to success.
“It’s not so much the fact that he comes to training first, but the way he works makes the difference,” the Juventus captain said.
“He pushes you to improve yourself. He is also very smart.
“He arrived in a different league and country, but immediately tried to understand the dynamics and integrate into the city.”
Chiellini accrued his 100th Italy cap at the weekend against Portugal, although Ronaldo was not in the squad due to rest.
Ronaldo, currently on 154 Portugal caps, will return to the national side next year, however.
“He will come back to the national team and he will be able to play even more than me,” Chiellini admitted.
“I have to manage myself.”