Cristiano Ronaldo is only 15 games into his return to Manchester and is already showing why both City and United wanted to sign him in the summer.

When it looked like City were about to pull off a sensational late transfer window swoop for Ronaldo, United got wind and made sure he would return to Old Trafford, with Sir Alex Ferguson and Rio Ferdinand among the Old Trafford legends personally intervening to make the transfer happen.

Fast forward three months and Ronaldo has shown exactly why City were ready to break with their usual long-term transfer plans to sign a 36-year-old at the last minute.

Ronaldo has 10 goals in 15 appearances, winning seven points for United as a direct result of his goals. Without Ronaldo, United would have five fewer points in the Champions League and be staring at the Europa League. With him, they won the group with a game to spare.

In the Premier League, they'd be two places lower without Ronaldo's goals, and he surely kept Ole Gunnar Solskjaer in his job for longer than he eventually got.

So why is there still an argument over Ronaldo's suitability in United's side? And why will City be watching on with their feet up relieved to have missed out on his signing?

If we ask Roy Keane and Jamie Carragher it's still to do with Ronaldo's infamous 'lack' of pressing, as well as United's targets this season. Despite his ridiculous goals record and super-human ability to win games on his own in the last minute, Ronaldo is still coming in for criticism due to his supposed disruption to United's balance.

So when caretaker manager Michael Carrick dropped Ronaldo to the bench for their 1-1 draw at Chelsea this weekend, it was inevitable that the Sky Sports studio would descend into a viral shouting match at full time.

This week, it was Keane and Carragher taking turns to shout louder than the other asking the same questions over and over to each other. The main gist of the 'debate' was that Keane felt Ronaldo's goal record was justification for his lack of pressing in a game, while Carragher believed Ronaldo's place on the bench was justified, and that if he wasn't signed to win United the title this season then perhaps he wasn't the best signing they could have made.

Both valid points, and it would be an interesting debate if conducted at a few decibels lower, and one exchange stood out in the clip that has been shared and shared in the last 24 hours.

Carragher asked: "Why did Man United sign Ronaldo in the first place? They signed him because he was about to sign for Man City. There was no plan to sign him. They signed him at the last minute."

Keane replied: "Not to go to City but to come and sit on the bench?"

Carragher: "The United manager is allowed to put Cristiano Ronaldo on the bench," to which Keane disagreed and the shouting continued.

It was the mention of City that has gone under the radar in the analysis of the 'analysis'. Yes, City would have benefitted from Ronaldo's presence and goals, just as United have, but imagine if Pep Guardiola had dared to put Ronaldo on the bench for a big game like a trip to Stamford Bridge.

At United, Ronaldo getting benched is a big story. At City, he would have to get used to it as a matter of course. He would also have to get used to pressing and playing for the team.

In fairness, Guardiola recently said Ronaldo and Lionel Messi are the only players in the world who can't be managed, but there would still be a level of expectation for what Ronaldo would have had to do off the ball at City.

If Ronaldo stormed down the tunnel after every game as he is doing this season, that wouldn't exactly go down well with a City support who adore their team collective that Guardiola has built.

And for all the talk of City's lack of striker, every passing game this season is proof that maybe the decision to go without a 'number nine' this season was justified, as every player in the squad knows the system in their sleep — and that is enough to score goals whoever plays centrally.

There's a fair argument that Ronaldo could have unbalanced that approach, as he's showing at United. And the furore over every decision made surrounding Ronaldo at Old Trafford is another reminder to the bosses at City that they don't need the drama that comes with someone like 'CR7'. City are showing once again, that a cohesive unit is much more likely to return trophies than a team of individuals.

They'd of course take his goals, but the league table shows that maybe City have had a lucky escape with Ronaldo.

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