Barcelona humbling leaves Manchester United with a mountain to climb this summer

In acres of space on the halfway line and under the floodlights of one of Europe's most captivating green carpets, Paul Pogba's decision to ditch the idea of orchestrating a cohesive attack for an audacious 55-yard punt at Marc-Ander Ter Stegen's goal summed up Manchester United's issues both on and off the field.

It reeked of a sense of absurdity, callousness, and perhaps most poignant of all was the disconcerting nature of one of the clubs most integral cogs decision making. Notwithstanding Lionel Messi's nonpareil approach on the night, a series of embarrassing moments meant United were successful in digging a hole for themselves, thereby exacerbating the effect of years of impotency associated with their recruitment and retention of players.

Ashley Young has rightly been the epicentre for all the United fans' rancour, and yet his outlandish and frankly embarrassing attempt at a Cruyff-turn so close to United's goal wasn't the singular most disturbing takeaway on a night which perfectly elucidated the gap between United and Europe's elite.

The fact that four of United's five members in the back-line at the Camp Nou were at the club when the Red Devils were knocked out of the Champions League by Basel in 2011 is enough evidence to substantiate the reality that United, for all of their fans' rebuttals, are a club in decline, and not in transition.

Ashley Young's mistake instigated a Lionel Messi masterclass at the Camp Nou

It's hard to point finger's at Ole Gunnar Solkskjaer's team selection or tactical nous at this moment. The Norwegian set up his team with the correct mindset and for the most part, effective tactics, which probably would've been carried out to perfection by players who were of a certain calibre, and those who weren't subscribed to the concept of selective accountability.

Once the exhaustive mysticism surrounding Solskjaer's exploits in Barcelona in 1999 and how they could provide a sturdy bedrock for the United players to replicate their own heroics in Paris faded out, the bare bones of this average United squad were brutally exposed by Ernesto Valverde's well-oiled side and Messi's routine splendour. Marcus Rashford missed an opportunity to put United back in the tie early on and his effort grazed Ter Stegen's bar.

Shortly after, Scott McTominay was presented with an opportunity to have a shot at goal from inside Barcelona's box, but the lanky 22-year-old midfielder failed to control the ball which was subsequently cleared away by Gerard Pique.

What followed after that was a spell of unmatched dominance and a level of football United couldn't match even if they played for another 90 minutes - such was the chasm in quality between the two sides.

Naturally, the humbling raised some pertinent questions about how United just cannot seem to catch a break and find any sort of stability - be it affairs off the pitch or on it.

Ruminating on the ball for far too long, Pogba, once again, failed to stamp his authority in a fixture which he was expected to dominate. It's getting to a point where it won't be unusual to consider Solskjaer's decision to build his United around the Frenchman.

Let's not get things twisted here - Pogba's natural ability and footballing intelligence places him in an elite bracket of midfielders in the world. However, the sticking point since his arrival at the club has been his tendency to embellish an encounter with glittering moments and not having a domineering hold over them.

This, coupled with Real Madrid's confidence is swooping in and luring him away to the Bernabeu, presents a predicament of its own for the clubs hierarchy and Solskjaer. Do they persist with him or do they cash in and bring in a couple of midfielders who could actually make the difference in big games consistently, suit the system to a tee and not need other players to unlock their true potential? It's a tricky terrain which Solskjaer will have to tread once the season ends and the transfer charades begin.

Pogba put in a characteristically poor performance against Barcelona.

Similarly pointed are concerns regarding United's bumbling and frankly incompetent set of central defenders and full-backs. Eric Bailly, after showing bags of promise and potential post his arrival from Villareal, has mysteriously fallen off a cliff and is at a crossroads in his United career, with an exit not completely out of the equation for the talented Ivorian in the summer.

The contract extensions handed out to Phil Jones and Chris Smalling become more perplexing with every passing game, whilst the paucity of exceptional full-backs is quite frankly baffling.

If United are to get anywhere near challenging the likes of Manchester City and Liverpool for the title next season, they need to be ruthless, shrewd, and extravagant, all at the same time, in their recruitment of a back-line in the summer.

Up front, an obtuse and inefficacious set of attackers who's combined goal tally this season (42 goals) falls three short of Messi's (45 goals) needs some serious replenishment. A charismatic presence on the right-wing at Old Trafford who can increase United's dwindling productivity from the wings and resuscitate United's right flank should be the reference point for an attacking overhaul.

Borussia Dortmund's Jadon Sancho and his full-blooded brilliance makes him an utterly enticing option, and according to reports in the English media, Woodward is willing to bite the bullet and spend a fortune on the former Manchester City academy starlet.

A whiff of unpredictability, workhorse like professionalism, incredulous dribbling ability and numbers to back up his envious end product vindicates United's pursuit of Sancho. After a tryst with big names who failed to rack up the numbers in terms of goals, it's time for United to go with what works for once and ditch their fixation for ignoring productivity and chasing personalities with a huge social media presence.

Sancho is United's primary target this summer.

What last night's humbling made abundantly clear is the magnitude of the job at Solskjaer's hands. As has often been the case for years now, this summer holds the potential to define United's future as venerated footballing giant.

Ed Woodward needs to swallow his pride and appoint a director of football who can assist United's Norwegian manager in recruiting the targets he wants and not settle for second-string acquisition's, as has been the case for a few years now.

Congruously, it is imperative that the Glazers set the cash coffers ringing and provide as much financial backing as they can to their manager - for anything less than a stellar transfer window this summer can have serious repercussions for United as a brand and more importantly, a football club looking to get back to the zenith of English and European football.