Alexis Sanchez on Monday finally signed for Manchester United, becoming the latest player to cross the great Arsenal-Manchester United divide, to spark wild celebrations among the traditionally exuberant Red Devils faithful.

Considering United have, the biggest fanbase in the world, there were, somewhat unsurprisingly, a deluge of celebratory posts that not so subtly hinted at the club’s resurgence.

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While the signing of the Chilean winger is indeed a steal, here’s why the Red Devils faithful should wait a while before exhibiting their ambidexterity to inundate various social media platforms:

Eye-popping wages to have a long-term fallout?

While clubs rarely disclose official wages, Sanchez’s pay check ranges from £300,000 to £500,000 per-week, according to media reports.

Even if one were to take the aforementioned details with a pinch of salt, there can be only one conclusion: Manchester United’s already-bursting-to-the-brim wage bill cannot be sustained.

And regardless of the fact that the club is a financial powerhouse, such an emolument for a player who turns 30 this year isn’t the most fiscal-savvy decision is it?

The Wayne Rooney situation is still fresh in memory and one shudders to think how the club will manage once Sanchez’s abilities begin to wane in a few year.

Despite the fact that Sanchez came on a relative bargain (straight swap for Henrikh Mkhitaryan), those wages are likely to spark disharmony in the dressing room.

David de Gea is perhaps the only world-class player United possess, while the likes of Paul Pogba and Romelu Lukaku are nearing that elite bracket.

All three are now below the Chilean in terms of their weekly salary and one can bet that De Gea and Pogba at least, will be demanding a hike in the summer.

Is Sanchez really the missing piece of the puzzle?

Derby rivals Manchester City have blown everyone away this season with their brilliant football, while United have been a distant second.

How the Red Devils faithful will be chafing at that, after getting accustomed to glory and entertainment in equal measure in the Alex Ferguson era.

For Pep Guardiola’s Sky Blues have dominated the Premier League in an unforeseen manner and are serious contenders for the UEFA Champions League as well.

In stark contrast, United have been functional at times, dour at others, as they have struggled to keep pace with City (12 points behind as of now) at the Premier League summit while they are nowhere near the likes of Barcelona and Real Madrid on the continental stage.

Sanchez is expected to slot in on either wing, with Jesse Lingard (for now) and Anthony Martial for company while Romelu Lukaku lines up at the apex of Jose Mourinho’s 4-2-3-1 formation.

A dream attack surely, but is the Chilean really the missing link United have been looking for ever since Alex Ferguson departed?

The Theatre of Dreams has put many a fan to sleep of late as their beloved Red Devils have struggled to return to their cavalier past.

On paper their attack looks set to thrill, but Jose Mourinho has never been one for an expansive style of play, preferring the adage “Attack wins you games, but defence wins you titles”.

A famous remark by a certain Scot (guess who?) who had a stellar managerial career in England, made even more ironic as it is perhaps most apt for the current United incumbent.

The Special One is not inclined to employ a free-flowing setup but in Sanchez he has a free spirit, not unlike Anthony Martial.

The Frenchman had a difficult first season under Mourinho and while he knuckled down to cement his place in the starting XI this campaign, one wonders if the Portuguese tactician will employ both the wingers together on a regular basis.

Sanchez is, at 29, a seasoned professional and will probably adjust to Mourinho’s methods far quicker than Martial, but nonetheless a big question mark hangs over the Chilean as the business end of the 2017-18 season nears.

For Arsenal and Barcelona, Sanchez’s last two clubs, play in a manner vastly different from the one Mourinho leans towards and it remains to be seen if the Chilean will be an instant fit at Old Trafford.

Of great expectations from No.7s

Yes, Alexis Sanchez joins an elite list of players to have put on the iconic No.7 jersey, in the company of the likes of George Best, David Beckham and Cristiano Ronaldo et al, but look closely and United haven’t had the best of luck with the number of late.

Antonio Valencia, Michael Owen, Angel di Maria and Memphis Depay have had far from satisfactory stints at United whilst donning the No.7 at Old Trafford.

While Valencia has been a magnificent servant for the club, the Ecuadorian struggled with the weight of the iconic number and switched to his original No.25 after a single season.

Di Maria, not unlike Sanchez, arrived in Manchester on the back of a stellar reputation and after a bright start, faded spectacularly before being packed to PSG at a cut-price.

And Memphis Depay, billed as United’s marquee signing when he arrived in 2015, flattered to deceive in the two seasons that he spent in England and was shipped off to Lyon without much fanfare in 2017.

To put it bluntly, United’s stature is perhaps incomparable with any side in the English top-flight and expectations are sky-high whenever they make a marquee signing.

For despite the relative bargain, Sanchez is a marquee signing, make no mistake.

For not only United outbid Manchester City (in terms of wages) to nab their man, they also sacrificed a likeable figure in Henrikh Mkhitaryan in the process.

Transferring in the middle of the season is never ideal and with everything that’s been going on, the United faithful will look to their new No.7 to drive them to titles in the months to come and the clock is definitely ticking for the mercurial Chilean.

Problem of plenty for Jose Mourinho

Much has been made of United’s offensive woes this season, for despite netting 49 goals (behind only Manchester City and Liverpool) in the Premier League so far, their fans have been crying out for more attacking endeavour, especially in big clashes.

While Sanchez’s addition gives them some sorely-needed firepower, don’t United have a plethora of attacking options already?

Juan Mata, Jesse Lingard, Marcus Rashford, Anthony Martial, Romelu Lukaku and Zlatan Ibrahomvic all ply their trade for Jose Mourinho’s men and Sanchez’s arrival will give the Special One a major selection dilemma.

Marcus Rashford, a United Academy product, has found playing time hard to come by this season due to the summer acquisition of Romelu Lukaku and resurgence of Jesse Lingard and Anthony Martial.

And Juan Mata may be a delightful player to watch, it’s not a secret that the diminutive Spaniard’s technical style isn’t exactly in line with Jose Mourinho’s philosophy.

With the World Cup less than six months away, every player will be desperate to get regular minutes under their belt and will be miffed if they continue to be utilised for cup competitions like the FA Cup only.

Mata and Rashford are the ones most likely to miss out, with Ibrahimovic almost certain to leave in the summer after an injury-wrecked 2017-18 season.

Competition for places is a good thing, but Sanchez is, at this moment at least, undroppable and the Chilean’s arrival may just cause create fissures in the otherwise tight-knit United camp.