From the moment the winter transfer window slammed shut, attention was immediately shifted to the summer – at the very highest level, at least.

For those competing within elite circles, there are just two openings every season in which to rebuild or restructure a squad.

As one door closes, another prepares to open – with scouting, assessing, reviewing and discussing a never-ending cycle that revolves from summer through January and back again.

It is, generally, during the off-season that the most considered work is done, with the winds of change often sweeping across Europe and the wider footballing world once the top divisions on the planet enjoy a well-earned break.

Taking that into account, banks will inevitably be broken again this summer, with the Premier League likely to lead the way when it comes to elaborate recruitment through multi-million pound deals.

There may yet be more twists and turns to be taken in the current campaign, but it is already apparent that the big boys will be splashing the cash this summer.

Chelsea, Arsenal, Liverpool, Tottenham Hotspur – all will be expected to spend, and spend big, once free to do so.

It is, however, in Manchester that the most interesting business could be carried out.

City, humbled once again during another lacklustre defence of the English crown, are an aging unit and one in serious need of an injection of verve and vigour.

United, meanwhile, have seen Louis van Gaal lay the foundations for future success, with it vital that they make the most of these building blocks and entice further world-class performers to Old Trafford in an effort to rekindle the glories of years gone by.

Among those whom both the blue and red halves of the city are said to be keeping an eye on is Kevin De Bruyne – a man no stranger to English football, but something of a former Premier League side note.

Denied the regular game time he craved during a forgettable two-year stint at Chelsea, the Belgian forward has reignited his flame in the Bundesliga – first during a loan spell with Werder Bremen and now with Wolfsburg.

Still only 23 years of age, De Bruyne has emerged as one of Europe’s most sought-after talents.

He has more than held his own in a division which pitches him into direct competition with Bayern Munich’s enviable array of attacking superstars – including wing wizards Arjen Robben and Franck Ribery.

It is difficult to see how either of those could be lured away from Bavaria, but De Bruyne would appear to be a more realistic target.

Yes, he has Wolfsburg pushing Bayern closest in the German top flight – with many Bundesliga betting markets, such as those at no longer offering a price on a top-four finish but delivering plenty of other options.

That means that they are heading back to the Champions League in 2015/16, but they will not be expected to do much in that competition and De Bruyne may be tempted to move on again and link up with a side holding a much stronger hand at the continental table.

City and United would fall into that category, and it is the former that have the greater need for a blockbuster signing this summer – with it no surprise, therefore, to see them heavily-fancied in the De Bruyne chase.

It is, however, easy to argue United’s case. Were they to move Angel di Maria and/or Radamel Falcao out, De Bruyne would slip seamlessly into the ranks – more of a Van Gaal-type player as one prepared to offer more to the collective cause.

Momentum is already gathering behind the Red Devils’ reported interest (per talkSPORT) and while City have the greater need and arguably the greater spending power, United may be the bigger draw and would like nothing more than to pip their arch-rivals to a top target and reassert their dominance in Manchester – silencing the ‘noisy neighbours’ once again.