In fact, talkSPORT pundit Jason Cundy has said 'I hope he fails'… and he won't be the only one.
The football world has been surrounded in Ronaldo hype ever since United announced his return on transfer deadline day earlier this summer.
The Portuguese superstar sealed a stunning move back to Old Trafford last month after 12 years away, with the Red Devils snapping up the superstar from Juventus for an initial £12million.
The 36-year-old claimed three Premier League winners' medals and one in the Champions League in his first stint at the club and continued to enjoy a trophy-laden career after leaving for Real Madrid and then Juventus.
Ronaldo has made a vow to United fans there will be more of the same now that he is back, insisting he has not returned 'for a vacation' and that he is 'here to win again'
Cundy, though, despite admitting his arrival is great for the 'stature' of the Premier League, says he - and most fans with the exception of United supporters - are hoping to see him 'fall flat on his face'.
"I understand and get the hype around Ronaldo, one of the greatest players to ever put a pair of football boots on," the talkSPORT host said on the Sports Bar.
"He's going back to the club that really made his name at Man United.
"I get all the hype and all of the romance and understand why United fans are excited, so they should be.
"I'm looking forward to seeing how he performs, but I hope he fails.
"I've said this before, I hope he falls flat on his face. He won't, but I hope he does."
The talkSPORT host isn't the only one, with British rock legend Noel Gallagher recently saying he's 'glad' Ronaldo didn't join his beloved Man City this summer.
Former Chelsea defender Cundy added: "No other fans want to see him do well. He's coming back and we're lucky to have someone of his stature come back to the Premier League.
"For far too long, Spain have had the best players - Messi, Ronaldo.
"I've seen my club [Chelsea], be pilfered and other clubs who have had to leave the Premier League.
"It's shifting and that's a good thing but, for me personally, I hope he fails."
The five-time Ballon d'Or winner, who will likely make his debut against Newcastle on Saturday, hinted he could be at the club until he's 40.
"This is why I am here," he said in an interview with the club's official website. "I am not here for a vacation.
"Before was good, winning important things and I wore the shirt before, many years ago, but I am here to win again.
"I am capable, me and my team-mates. I am ready to go, I am ready to go. It is a good chance for me, for the supporters, for the club, to get one step ahead.
"I am ready and I think I will be a huge thing in the next three or four years."
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