The Argentine striker couldn’t even hold down a regular first team place when he was at Old Trafford, so would stand little chance of doing so in a side combined of United and City.

Indeed, the £25m man would have a job just getting on the bench with Dimitar Berbatov, Michael Owen, Craig Bellamy and Roque Santa Cruz all vying for places in the squad.

If that’s the talent that didn’t make the cut, how about those that did?

A forward trio of Wayne Rooney, Emmanuel Adebayor and Robinho would have the perfect mixture of power, technique, mobility and goals.

With Adebayor as the pinnacle and Rooney and Robinho dropping off or stretching the play out wide, they would be impossible to contain.

The trio scored a combined 48 goals between them last season, with Rooney and Adebayor already looking like bettering their totals of 17 and 16 respectively with explosive starts to this term.

To accommodate a three-pronged attack, Manchester’s dream team would have to deploy a three-man midfield.

I’ve gone for an attacking engine room but one filled with players willing to put in a shift, like Ryan Giggs and Stevie Ireland. Still there will be a lot of onus on the only recognised enforcer in Darren Fletcher, who just gets the nod over Gareth Barry.

It was a close call between the two, with Fletcher just edging it having established himself as a top-class box-to-box midfielder.

His performances against Arsenal in last season’s Champions League semi-final is all the evidence you need to prove that he deserves a place.

Right now, it is difficult to imagine anyone other than Chelsea in the Premier League not finding a first-team place for Fletcher.

Owen Hargreaves would be another shout for the anchor role – but much would depend on the England midfielder’s ability to recover from career-threatening double knee surgery.

What the midfield lacks in muscle it more than makes up for in technique and creativity. With Giggs and Ireland, it is full of invention and goals – and, crucially, the ability to retain possession.

The back four has to be United’s.

Sir Alex Ferguson’s hat-trick of Premier League titles and back-to-back Champions League finals has been built on the rock solid central defensive partnership of Rio Ferdinand and Nemanja Vidic.

It is hard to see either Kolo Toure or Joleon Lescott breaking up that partnership - especially given their shaky start to the season.

Patrice Evra has proved himself Europe’s finest left back and offers plenty of attacking threat on the left, which will be needed with the lack of width in the midfield.

On the right, it was a tough choice between Wes Brown and Rafael da Silva.

Like Evra, Rafael’s attacking qualities would be a big bonus - but Brown’s greater sense of his defensive responsibilities gives him the edge.

And behind them there was only one choice.

With Ben Foster struggling to prove he is the man to succeed Edwin van der Sar with some shaky displays this season, Shay Given is an absolute shoo-in.

The former Newcastle goalkeeper stands alongside Petr Cech as the best in the Premier League and how Ferguson must be kicking himself that he didn’t make a move for him when Mark Hughes did.

Any pub bore, any barber, any taxi driver could have told you that any combined Manchester XI would be simply United, with the occasional dash of Blue thrown in.

Maybe someone like Uwe Rosler, Georgi Kinkladze or Paul Lake might have got the odd game, but the all-conquering Reds would simply have enveloped their struggling neighbours in any merger of the playing staffs.

But that has changed - dramatically - and it is all down to the petro-dollars of Sheikh Mansour and the astute transfer policy of City boss Mark Hughes.

These days there is real, honest debate going on in those pubs, barber shops and taxis.

Based on the performances so far this season, Shay Given would have to claim the goalkeeper's jersey, for starters. Edwin van der Sar has been a modern great but he is coming to the end of an illustrious career, is subject to the odd rick, and has been out with a hand injury which has left Ben Foster exposed.

By contrast, Given is reaping years of experience in the Premier League and has been outstanding for the Blues, an extraordinary shot-stopper and a keeper with real authority.

In front of him, the job gets tougher. Both sides have had problems with their defences this season, as evidenced by the Manchester derby, with seven goals leaked in total - it made for a classic but not if you were Micah Richards or Rio Ferdinand.

Right back has posed problems for both teams, with Richards left out after his Old Trafford wobble and John O'Shea doing a decent job for the Reds in a position which has become a problem for them as well.

But Pablo Zabaleta's form since replacing Richards has earned him a recall to the Argentina squad - and he is the kind of awkward, obstructive, competitive defender that any team needs.

Left back has to be Patrice Evra, one of the best in his position in the world, a consummate attacking force and a quick, dogged defender - Wayne Bridge is powerful going forward but not always convincing on the back foot.

Centre back is also an area which has been tossed into the air this season. Over the last two years, Rio Ferdinand and Nemanja Vidic have formed one of the best, most balanced, defensive partnerships in world football. This season, affected by injury and each other's absence, both have suffered serious blips. Kolo Toure, by contrast, has been a rock for City, and has emerged as a powerful dressing room leader, and on current form gets the nod.

With Joleon Lescott not yet vindicating his £24m price tag at City, and Jonny Evans still some distance from fulfilling his potential, Vidic squeezes in - his inconsistency will dry up as the season progresses.

United have traditionally had a powerhouse midfield but this season do not look as impressive as in recent times.

Darren Fletcher has been the pick - he has matured into a fine give-and-go merchant, the man who keeps the Reds ticking, and he gets a place.

But he has to be shunted over to the right-hand side to accommodate the central duo of Gareth Barry and Ryan Giggs.

It is not ideal to have two players who favour their left foot, but Barry has been the architect of City's brilliant start to the season and is emerging as the lynchpin of Fabio Capello's England midfield, while Giggs is enjoying a glorious Indian summer to his incredible career.

That clears the way for Craig Bellamy, a man who has defied the odds to claim his City place, terrorised the Reds on derby day and has been breathtaking for City this season - his link with fellow Welshman Giggs, and Evra, would be a sight to behold.

That leaves the strikers, and the choice is curiously simple.

Emmanuel Adebayor has been on fire for City, reviving the kind of form which made him one of the world's most feared strikers - a tall target man and a pacy predator rolled into one.

The prospect of pairing him up with Wayne Rooney, a skilled footballer with a street fighter's attitude, is one which would thrill any club manager.