The 36-year-old returned to the club he shone for during six medal-laden seasons on deadline day, joining from a Juventus in a deal that could reach 23million euros (£19.6m).
Ronaldo signed a two-year contract with the option of a further season and trained at Carrington this week, having been released early from Portugal duty and completed quarantine.
Now the veteran is primed to make his first appearance for United since joining Real Madrid in 2009, with Solskjaer confirming he will feature against Newcastle at a vibrant Old Trafford.
“He’s been good,” former team-mate Solskjaer said of Ronaldo’s early impact back at the club.
“Of course we’ve followed his career from afar since he left here and I think everyone’s very, very happy to have him back.
“He can speak for himself but he seems like he’s happy to be back as well.
“The mood’s been very good, he’s worked well and we’re looking forward to Saturday, of course.
“He’s been having a good pre-season with Juventus, he’s played for the national team, he’s had a good week with us here.
“He will definitely be on the pitch at some point, that’s for sure.”
Old Trafford will be rocking as fans celebrate the return of a player who was reportedly edging towards a move to Manchester City until United swooped a fortnight ago.
Ronaldo said he was “back where I belong” and spoke of his “never ending love” after rejoining a club he will add to both in terms of attitude and aptitude.
“We have grown as a group the last few years, I have to say – the determination, the desire, the focus has improved over time and bit by bit,” Solskjaer said.
“Even like bringing Raphael (Varane) in, he’s come in with a winner’s mentality, an unbelievable focus.
“Then of course Cristiano comes in as well and there’s no place to hide when you’ve got winners like them. You can’t go into training and give 95 per cent or not being focused.
“That’s what he demands of himself and of everyone else, so it’s been great having him in.”
Solskjaer can see Ronaldo playing into his forties like fellow United great Ryan Giggs, who adapted his game to remain effective at the top level.
The Portuguese has altered his game since leaving Old Trafford and returns 12 years later as the focal point of an attack whose set piece takers may have changed.
“You know, everyone evolves and develops throughout their career,” Solskjaer said.
“Of course Cristiano is a different player to (the) one who left but he’s in such good nick still and he will be looking at the next few years to play as much as he can, to score as many goals as he can.
“He’s a threat from direct set plays himself but also to be on the end of crosses and he’s adding something extra.
“We haven’t got his skillsets in the team, the mix of his skillsets – well, no one has, really, because he’s one of – if not the – best players that’s ever played the game.”
Anticipation is huge ahead of Ronaldo stepping out in a red shirt once more on Saturday, when the returning hero will also be back in the number seven shirt after Edinson Cavani gave it up for him.
“It’s one of these things that Edinson has been remarkable (with), (he) played really, really well last season,” Solskjaer added.
“Cristiano was ringing Edinson and they speak with each other. To pass off his shirt, it just shows the respect he’s got for Cristiano but also Cristiano speaking to Edinson shows the respect the other way.
“Two top, top professionals and players, and human beings.”
A former United captain is looking to spoil Ronaldo’s big day, with Steve Bruce hoping Newcastle can act as party poopers.
“It’s always going to be tough and obviously the added spice of Ronaldo coming back has added to it,” the Magpies boss said.
“But make no mistake, they’ve got quality players all over the pitch, so whenever you go to Old Trafford, the one thing you’re going to have to do is enjoy the challenge of playing against one of the big, big teams of this country and relish the opportunity to go and see if we can spoil the party a bit.
“That’s the big challenge to us all, of course, the ability for all of us to enjoy upsetting the apple cart and going and making it as difficult an afternoon as we possibly can for Ronaldo or Manchester United or the rest of them.
“They’ve got quality players all over the pitch and it’s one of those where you should really, really relish the challenge that’s coming and I hope we respond to it and really have a good go at it.”