The Portugal superstar netted a first-half brace to help Juventus to a 2-0 win over the Rossoblu.
Pirlo, who himself was a revered player during his playing days, hailed Ronaldo as someone who sets 'the example for everyone around him'.
"He is a great professional, as we already knew," Pirlo told DAZN, according to Goal.com
"He is a real champion and sets the example for everyone around him, both in the matches and in training.
"The only advice I can give him is to keep going in the same way."
The quick fire double over the side from Sardegna was the veteran's eight goal across six matches in all competitions at this juncture of the campaign.
Juventus will look to cement a spot in the UEFA Champions League knockout stages with a victory at home to Ferencvarosi TC on Tuesday.
