After completing his blockbuster move from Juventus at the end of August, fans have been eagerly awaiting the news of when the Portuguese star could make his second debut for the club.
Confirmation is yet to be given but it looks increasingly likely that Saturday's clash with Newcastle could be the day as the 36-year-old aims to announce himself as United's top talisman for the season ahead.
Ronaldo's ability to provide goals, assists and memorable moments is bound to get fans on the edge of their seats and it'll be the same for several players in the United dressing room.
While some will hugely benefit from playing alongside someone like CR7, others could struggle with the club's new top dog bound to change the way in which the team functions.
Here are the winners and losers from Ronaldo's United return…
Winners
Mason Greenwood
The young England international will undoubtedly benefit from the arrival of Ronaldo.
Greenwood is one of the sharpest finishers at United but at 19 years of age it's clear that the forward will be looking to improve both on and off the field.
If he can work closely with the Portuguese star and get a few ideas on how he can take his game to a new level, it could be hugely beneficial for a undoubtedly bright future ahead.
Marcus Rashford
Another player who will reap the benefits of playing alongside Ronaldo.
Rashford is a player who will no doubt form part of Ole Gunnar Solskjaer's new-look attacking line but thanks to the addition of the 36-year-old, he'll no longer be pressured by the idea of trying to be the club's main goalscoring threat.
Without that pressure on his shoulders, the addition of Ronaldo could free up Rashford to play his natural game, something that may even end up benefitting his goal return in the long run.
Ole Gunnar Solskjaer
A man who will be absolutely delighted at having done this deal.
Solskjaer has overseen huge improvements in United's squad since taking charge but if they're going to challenge for major titles then they need someone with that x-factor.
Ronaldo epitomises exactly that and with goals, assists and positive influence around the club, Solskjaer will be hoping that this signing could set his side up for a great campaign.
Losers
Bruno Fernandes
An international teammate of Ronaldo, Fernandes could be a player who is directly impacted by the new arrival.
The Portuguese midfielder has made his name at Old Trafford for being a key source of goals and assists for the club, many of which have come from the penalty spot.
With Ronaldo having his sights set on being the Premier League's top goalscorer, there is every chance that penalty-taking duty could be offloaded to the 36-year-old, much to the likely displeasure of United's current prime goalscoring threat.
Jesse Lingard
The England midfielder is a player who has found himself on the fringes of the first team of late, leading to speculation that he was in discussions over a move away during the summer.
With Ronaldo now joining the club it seems that first team opportunities could be even more limited for Lingard.
Lingard's contract is due to expire at the end of the season and perhaps the arrival of Ronaldo could be what seals the 28-year-old's fate with regards to a permanent move away.
Anthony Martial
The French forward has really struggled of late with a lack of form and fitness seeing him drop right down the pecking order at United.
Martial was going to struggle for regular starts this term regardless of what happened, but the signing of Ronaldo means that his stock has fallen even further.
Expectations for the 25-year-old are pretty low this term and that could well mean even fewer appearances for a player previously tipped as a future star.