Steve McClaren, who worked under Sir Alex Ferguson when the team won the treble in 1999, says the Portugal captain is a leader and has even been compared to one of the club's legendary captains.
Since re-joining the club this summer, Ronaldo has had a huge impact on the team's results with nine goals in 12 appearances.
Spearheading their attack, the 36-year-old is trying his upmost to help United win their first trophy since 2017.
"He's all about winning, and he knows how to win," McClaren told talkSPORT.
"Manchester United and Ole have brought him in to that dressing room to teach everybody else, this is what it takes to win.
"They've got to follow suit, the rest of the team."
Despite his excellent start to the season, United aren't hitting the same heights many expected them to be and it's up to the Solskjaer to find the right hymn sheet they can all sing off.
"Ole has to find a way to integrate Ronaldo and get that team playing as a team because they aren't doing that at the present moment.
"But once they find the solution and once they do that, my God they'll be quite unstoppable.
"I saw his body language (following the 2-2 draw against Atalanta) and he's remonstrating with players.
"He reminds me a little bit of Roy Keane, Roy used to do that. He's a winner and that's what he wants from the team."