The bombshell interview - due to air on Morgan's TalkTV show on Wednesday evening in the UK - has been trickled out to the public via The Sun and a series of social media trailer snippets, causing outrage amongst pundits and fans of the club.
The Portugal star, who has since joined up with his international teammates in preparation for the World Cup, also claims he "has no respect" for manager Erik ten Hag and that United's owners only care about making money.
The 37-year-old also took aim at former Manchester United teammates Wayne Rooney and Gary Neville, stating "they are not my friends", much to the former England duo's bemusement.
It seems as though it's a deliberate plot on Ronaldo's part to burn bridges with the club that helped forge his inimitable legacy, seemingly with the hopes of securing a swift move to pastures new.
But as fans of United are left fuming and stewing over their icon's unfiltered betrayal, Flashscore looks at how it stacks up against some of football's other most treacherous moments.
Sol Campbell (2001)
A Tottenham youth product, club captain, commanding England international and bright spark in an otherwise unremarkable period in Spurs' history, Sol Campbell vowed he would never join arch-rivals Arsenal in a post-match interview as speculation began to mount over his soon-to-be expiring contract.
Spurs were relatively light in the pockets at that time and, while reluctant to see their most-valuable asset go, had hoped to at least command some sort of fee before Campbell opted to leave on a newly-coined 'Bosman transfer' (aka, a free transfer).
He then famously did the unthinkable, signing for Tottenham's north London rivals Arsenal - who themselves were already in the midst of enjoying some of the most successful years in the club's history under Arsene Wenger - for the prize sum of absolutely zilch. To rub salt in the deepest of wounds, he went on to clinch the second of his two Premier League trophies for the Gunners at... White Hart Lane.
Spurs fans still sing some rather nasty songs about their perceived 'Judas' to this day.
Luis Figo (2000)
Many megastars of football have played for both of El Clasico's Spanish giants but few made the direct jump across the picket line. Figo was one such man to make the move - helping Madrid to christen their impending Galacticos era.
Figo moved from Camp Nou to the Bernabeu for £37 million - a world record at the time - but Barça fans were relentless in their abuse of the Portuguese icon when the two sides met, famously hurling all manner of objects - notably a severed pig's head - at the player whenever he lined up to take a corner.
Raheem Sterling (2015)
The summer of 2015 saw one of England's brightest young stars in Sterling leave the Reds - a place where his development was seemingly flourishing - with a lengthy and toxic transfer saga ultimately ending up in a move to Manchester City.
Having rejected a juicy £100k-per-week deal from Liverpool, a sizable sum for a 20-year-old, and with his agent making rude remarks about club legends, fans began to turn. Sterling then gave an unauthorised and controversial interview stating that "he wasn't a money-grabber", before securing a £49 million move to the very wealthy Citizens.
Emmanuel Adebayor (2009)
After a decent, if unremarkable stint at Arsenal, the Togolese forward fell out with manager Arsene Wenger and was swiftly sold to newly enriched Manchester City.
Ade would then claim he was forced out by the Gunners, which was refuted in a press conference the next day by Wenger, who revealed the striker had simply demanded too much money to stay. Adebayor would later publicly claim that he "hated" Arsenal.
Later that season, Adebayor would score against his former side and run the entire length of the pitch in order to knee-slide in front of a very aggravated stand full of Arsenal fans.
He'd even go on to play for Spurs later in his career as well, just to rub it in.
Ashley Cole (2006)
One of the murkiest transfers in the history of English football (which says a lot), Ashley Cole once claimed "he almost crashed his car" upon learning Arsenal were offering him a paltry £55k-per-week to remain.
Cole was undoubtedly one of the best left-backs in world football by this point and felt offended by the proposal, which was only £5,000 a week more than his current contract. A season later he moved to fierce London rivals Chelsea, but the move was not without its complications.
The Blues, under the guidance of Roman Abramovich and Jose Mourinho, were caught out in a 'tapping up' scandal that dominated back pages for weeks. Chelsea were fined £300,000, Mourinho was ordered to pay £200,000, and Cole himself was fined £100,000 "for his compliance" - leading to the nickname "Cashley" being sung on terraces for the foreseeable future.
Dimitri Payet (2017)
The Frenchman caught the attention after his move to West Ham in 2015, lighting up the Premier League with dazzling tricks and stunning goals. Hammers fans were loving it, having not seen his likes since the long-gone days of Paolo Di Canio.
It was to end on a sour note, however, as within two years the mercurial attacker was pushing for a move to Marseille despite signing a five-year deal just months prior.
The then-West Ham boss, Slaven Bilic, stated that Payet was refusing to play for the club, and he was eventually left to make his move. Payet would later claim he was "bored in London" and felt his career "would regress" if he had stayed - although in recent times he's backtracked on those comments.
West Ham fans haven't forgotten, though.
Ahn Jung-Hwan (2002)
The South Korean's golden goal against Italy in the 2002 World Cup sent the co-hosts and their fans into raptures and provided one of the feel-good moments of the entire tournament.
Unfortunately for Ahn, he played for Perugia. In Italy. And it didn't go down so well.
Perugia's owner, furious that his player had, quote, "ruined Italian football", cancelled the Korean's contract the next day, with the Italian club refusing to pay his salary.
After a moment of clarity, Perugia did eventually try to reinstate the player's loan contract into a permanent one, but the damage had been done and Ahn decided to move to Japan to ply his trade instead.
Diego Maradona (1990-91)
One of the more dramatic entries on the list, Diego Maradona's storied time at Napoli came to an abrupt halt around the time of the 1990 World Cup in Italy.
Already a controversial figure, when it came to his Argentina side facing the hosts in the semi-finals, Maradona did his best to rile up an often belittled Naples region and turn them against their Italian compatriots. Argentina knocked Italy out and cultural chaos would ensue, with newspapers calling for his exile from the country.
What followed was even worse as mafia links, kiss-and-tells, exposure of his cocaine use and his fathering of an illegitimate child all surfaced, leading to a shameful and sad ending to an otherwise beautiful football story at Napoli.
Time heals, however, with a plethora of city murals and a renamed stadium now honouring the late maestro.
Hossam Ghaly (2007)
Tottenham fans still haven't forgotten the moment Egyptian midfielder Ghaly threw his shirt down after being substituted by then-manager Martin Jol in a Premier League game against Blackburn.
Ghaly had only come on as a sub after 29 minutes but faced the humiliation of being brought off again half an hour later, replaced by Robbie Keane.
A furious Ghaly threw his match shirt on the floor in disgust before walking down the tunnel to an echo of boos and chants of "you're not fit to wear the shirt" from the White Hart Lane crowd.
Jol's decision was vindicated as Keane went on to score the equalising goal. Ghaly never played for Spurs again and ultimately disappeared into relative footballing obscurity.
Romelu Lukaku (2021)
Saving the most recent example for last, much excitement and clamour surrounded the second coming of Romelu Lukaku to Chelsea in 2021.
A career filled with mixed stints at Everton and Manchester United, the Belgian forward had seemingly found his golden touch under Antonio Conte at Inter Milan and was once again living up to the promise many had always expected of the big striker.
Things didn't go quite according to plan for Lukaku under Tuchel, with a slow start drawing criticism over his work rate and ability to perform in the Premier League.
An ill-timed interview with Sky Italia made things much, much worse though, with the Belgian blindsiding Chelsea with comments questioning both Tuchel's tactics and managerial authority, as well as suggestions he regretted his £90 million move from Italy.
Tuchel was forced to answer some difficult questions in the following press conferences, and after some lengthy behind-the-scenes conversations, Lukaku eventually came out to apologise for any hurt that his comments had caused Chelsea fans.
Things never really got much better though, and he was strangely loaned back to Inter Milan just a season later, with many at Chelsea barely speaking of him since.
