If there were any illusions, Manchester United now know how far they must travel under Ole Gunnar Solskjaer. The gulf that exists between them, and the elite of the European game.
A panicked opening two minutes aside, this was as comfortable as the scoreline suggests, the game never in doubt after 20 minutes when a horrible mistake by David de Gea gifted Lionel Messi his second goal of the night.
By the end, the weakness in this United group had been heartlessly exposed: not just those who might be felt lightweight in this company, but those who believe they belong.
Lionel Messi can’t stop smiling after giving Barcelona a two-goal lead after just 20 minutes at the Nou Camp
The Argentine skipped through to the edge of the Manchester United box before sending a fairly tame shot at goal
However, Messi’s shot slipped through the grasp of David de Gea to gift the Catalan giants their second goal of the game
United’s Spanish goalkeeper hunches over after making a rare mistake to give Barcelona their second goal at the Nou Camp
MATCH FACTS, PLAYER RATINGS AND MATCH ZONE
BARCELONA: (4-3-3) Ter Stegen 6.5; Sergi Roberto 6 (Nelson Semedo 71, 6), Pique 7, Lenglet 6.5, Jordi Alba 7; Rakitic 7, Sergio Busquets 7, Arthur 7 (Vidal 75, 6); Messi 9, Suarez 7, Coutinho 7 (Dembele 81)
SUBS NOT USED: Cillessen (GK); Malcom, Umtiti, Alena
GOALS: Messi (16, 20), Coutinho (61)
BOOKINGS: Suarez (77)
COACH: Ernesto Valverde 8
MANCHESTER UNITED: (4-3-3) De Gea 4.5; Jones 5, Lindelof 5.5, Smalling 5, Young 5; McTominay 6, Fred 4.5, Pogba 5.5; Lingard 5.5 (Sanchez 80), Rashford 6.5 (Lukaku 73, 6), Martial 4.5 (Dalot 65, 6)
SUBS NOT USED: Romero (GK); Mata, Andreas Pereira, Matic
COACH: Ole Gunnar Solskjaer 6
REFEREE: Felix Brych (Germany) 7
MAN OF THE MATCH: Lionel Messi
VENUE: Nou Camp
*Ratings by Chris Wheeler at the Nou Camp
For more of Sportsmail’s fantastic MATCH ZONE feature, please click here.
Lionel Messi breaks the deadlock with a superb solo effort by firing a left-footed shot into the bottom corner of the net
Philippe Coutinho (No 7) arguably scores the goal of the game after finishing off a well-worked Barcelona move with a long-range effort to make it 3-0 on the night
Errors from Ashley Young and Fred led to goals, but if Real Madrid were watching the performance of Paul Pogba they will not have seen a player who looks capable of wrestling domestic superiority from Barcelona.
He was overrun, without influence and on one occasion desperately self-indulgent. Yet he is far from the only problem. When Alexis Sanchez came on to a warm reception with 11 minutes to go, it was a reminder.
The player that United broke the bank to recruit is in essence a Barcelona cast-off. Those that are good enough to make it at Nou Camp will not be leaving for Old Trafford any time soon. Barcelona is the home of the best in a way Manchester United has not been for some time now. And that showed.
Messi had not scored at the quarter-final stage of this competition since April 2013 against Paris Saint-Germain – although he has had 50 shots in the interim – but he made up for it here.
As for Philippe Coutinho, any thoughts that he may regret his move from Liverpool, were overwhelmingly countered. His goal gave the scoreline the emphasis it deserved.
Messi blows a kiss to the stands at the Nou Camp after superbly breaking the deadlock with a brilliant solo effort
The Barca talisman nutmegged United midfielder Fred before sending a wicked left-footed shot into the bottom left corner
Messi watches his shot nestle into the inside side netting of De Gea’s goal with the Spaniard unable to reach the shot
Messi (left) celebrates with Philippe Coutinho (right) after the Argentine gave Barcelona an early lead on Tuesday night
Messi played a long crossfield ball from deep in his own half to Jordi Alba, who found Coutinho on the overlap inside. He cut towards the centre once more and struck a delightful curving shot, high and over the reach of De Gea.
If Barcelona were disappointing at Old Trafford, this win and the 4-0 aggregate outcome are a reminder of the standards they continue to set. Standards that United can only dream of reaching right now.
They have a cult figure as manager, a grand history, and a growing mythology that links the two, but what they miss is the quality setting Barcelona apart.
Ole may be at the wheel, but he’s not steering a high performance vehicle. The idea this could be United’s year, as it was for Chelsea and their unlikely steward, Roberto Di Matteo, in 2012, was quickly dispelled.
Bottom line: they couldn’t live with Barcelona after a sprightly first two minutes. In that period United took their hosts by surprise, hit the bar and fumbled a second good opportunity. Had either of those chances gone in, who knows?
Coutinho made it 3-0 with a fantastic long-range effort as De Gea was beaten all ends up in the United net
The former Liverpool playmaker hit his effort from outside the box which flew into the top-right corner of the goal
Coutinho is congratulated by his Barcelona team-mates after scoring their third goal of the night and fourth of the tie
The Brazilian celebrates by raising a finger to the crowd while Rashford (right) waits to restart the game
Yet if there is one thing we know about visiting Barcelona: take your chances because they are going to take theirs. Well, enough of them, anyway. Let’s face it, if Barcelona took every chance that came their way they would have goal difference measured in the hundreds each season.
So when Marcus Rashford broke through after just 35 seconds and, instead of a firm low finish, chipped and clipped the bar of Marc-Andre ter Stegen, there were immediate thoughts it could be a pivotal moment.
So too the pass that found Scott McTominay in a ridiculous amount of space immediately after. The ball got trapped under his feet and the danger passed; and with it the hopes of Manchester United.
When Barcelona first scored United could content themselves with the knowledge the mission hadn’t changed: they still needed to score twice to progress, as at the start.
The second, however, was a killer. Now United needed three in Nou Camp, against a team that had not surrendered a first leg lead at home in European competition since succumbing to Metz in the 1984-85 European Cup-Winners Cup. And there was nothing beyond that first two minutes that suggested United had surprise in them.
It wasn’t just the errors that lead to the goals that highlighted the difference. In the ninth minute, United had the glimmer of a break on.
Ivan Rakitic (centre) goes down inside the United box under the challenge of Fred (right) in the first half
Match official Felix Brych points to the penalty spot after deeming Fred’s challenge as a foul inside the area
United players surround the German referee after he awards Barcelona a penalty during the first half
After being advised to review the decision by VAR, Brych watches the incident again over at the side of the pitch
After watching replays of the incident, Brych overturns his original decision and signals that no penalty has been awarded
The ball fell to Pogba in the vicinity of the centre circle: and he shot at goal. Would a Barcelona player have tried such a stunning piece of self-indulgence?
The ball flew high and harmless, over the bar, ter Stegen’s recovery never in doubt. It wasn’t the action of a player thinking of his team – and Barcelona are, first and foremost, a team. A very, very good team.
With one quite extraordinary individual, obviously. Yet Messi never plays as if the event is about him, even if his genius often makes it so.
He does not go it alone, if a team-mate is better placed, he doesn’t always occupy position A. And yet, operating as a deep lying forward, he is averaging better than a goal a game this season. Incredible.
First, before the Messi show, United had to survive a penalty call. Fred got a foot in, and in doing so sent Ivan Rakitic rolling, rolling, rolling, like a ball on a downward slope at Augusta National but with less assistance from gravity.
Messi came close to grabbing his hat-trick but his overhead kick went just wide as Suarez tries to get out of the way
Marcus Rashford came close to breaking the deadlock inside 60 seconds after his shot hit the crossbar
Paul Pogba acknowledges the match official after he is pulled up for a foul on Arthur in the first half
By the time the Croatian came to rest referee Felix Brych was pointing to the spot. At which point VAR did its thing and Brych trotted over to see confirmation of his judgement.
And a good thing he did. In the first replays the tackle looked good, in the second it looked like a foul, but a close up of Fred’s foot as he made his challenge showed he won the ball. No penalty. Justice done. Not that it mattered; within ten minutes United were 2-0 down.
The first goal started with Young getting in a tangle that served up the ball to Messi. The pair had shaken hands as captains before the game and one can only hope Young made the most of that gentle moment. His other engagements with the player were more fraught, to say the least.
Messi beat Fred and glided past Phil Jones who, with his white plaster headband appeared to come pre-injured, probably to save time. He shaped to shoot and Chris Smalling put his arms behind his back to guard against handball.
Scott McTominay (left) tries to dispossess Barcelona centre back Clement Lenglet (right) during their clash at the Nou Camp
Luis Suarez bursts past United’s Brazilian defender Fred during the opening stages of the second leg at the Nou Camp
Pogba is brought down by Rakitic (right) as United had everything to do in the first half of their second leg in Spain
He needn’t have bothered; Messi doesn’t hit it near enough to obstacles for this to be a problem. He curled it sweetly out of De Gea’s reach. There was nothing the finest goalkeeper in the English game could do. Sadly, the same could not be said of his second goal.
The blame lies with De Gea but, for United, problems began when Fred attempted a Cruyff turn perilously close to his own penalty area. Frankly, Cruyff wouldn’t have attempted a Cruyff turn in that position – and he was better at them than Fred.
So the ball was lost to Messi, who again left Jones in a metaphorical tapas bar downtown and hit the ball low. It wasn’t his finest effort and should have been easily stopped but the often infallible De Gea made arguably his biggest error since his first season in English football.
His weakness then was crosses and the physicality of the English game, but no such excuses here. This was a simple shot and the ball squirmed horribly underneath his body. He reappeared after half-time to find Barcelona’s fans bowing down in mock admiration. It was a sobering night all round.