The Portuguese was handed a start for the Red Devils' Premier League clash on Saturday as they take on Newcastle at Old Trafford.
Ronaldo is starting alongside Jadon Sancho in what is a very attacking line-up from manager Ole Gunnar Solskajer.
Paul Pogba, Mason Greenwood and Bruno Fernandes are likely to have the visiting fans fearing the worst.
THE LINE-UPS
Man United: De Gea, Wan Bissaka, Varane, Maguire, Shaw, Pogba, Matic, Greenwood, Bruno Fernandes, Sancho, Ronaldo
Subs: Lindelof, Bailly, Mata, Martial, Lingard, Fred, Dalot, Heaton,
van de Beek
Newcastle: Woodman, Manquillo, Hayden, Lascelles, Clark, Ritchie, Willock, Longstaff, Almiron, Joelinton, Saint-Maximin
Subs: Schar, Lewis, Hendrick, Krafth, Fernandez, Murphy, Darlow, Gayle, White
It's not the first time he's walked onto the Old Trafford pitch since completing his sensational return - Ronaldo declaring 'I'm home' in a Man United social media post earlier this week.
He drove Man United to huge success during his first spell at the club and former teammate Wayne Rooney is backing Ronaldo to deliver more.
Asked what impact Ronaldo could have, Rooney said: "An enormous one, I think he's still one of the best players in the world.
"I think we've seen in the game against Ireland that's what he does, last couple of minutes he scores two goals, two great headers, so he can have a massive impact on this league."
talkSPORT will be bang across Ronaldo's second Man United debut with Adrian Durham presenting GameDay Live from Old Trafford.
Follow all the action here with talkSPORT's live blog.
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