Lionel Messi puts Manchester United back in their box as Barca fans revel in Cristiano Ronaldo woes

Ole Gunnar Solskjaer was haunted by his greatest hunting ground. And perhaps his own great expectations. After the artificially inflated nature of Manchester United's 3-1 win at Paris-Saint Germain in the last 16 came a chaotic night of home truths and wincing blows in the Camp Nou.

Barcelona, inspired by another mosaic Lionel Messi offering, ended the quarter-final mismatch so far ahead of Solskjaer's team that the Barca diehards were more gripped by Cristiano Ronaldo’s suffering in Turin than their own team binging on a full English for supper.

It was an indictment of how poor United were that they were left alone to wallow in their own grief after the former Liverpool man Philippe Coutinho had whistled a long ranger beyond the hurting David de Gea to make it 3-0 on 61 minutes.

Like United, the minds of home followers had wandered from the job at hand long before closing time.

The news of young Dutch upstarts Ajax brutally wiping the floor with arch enemy Ronaldo’s Juventus elicited a bigger cheer from the Catalan public than even Messi, chasing his latest hat-trick, could muster. If Carlsberg did Champions League nights and all that jazz.

God giveth, and God taketh away. Almost exactly 20 years after he had famously won the Champions League in injury time for United against Bayern Munich at this cavernous venue, here Solskjaer was left to contemplate how far United have slipped from relevance.

The visiting fans perched in the Gods were closer to the heat than most of United’s players, particularly blokes such as the poor strapping stopper Phil Jones, whose need to wear a Rab C Nesbitt headband only highlighted his inability to cope with genuine pace, movement and menace. Unlike the Scottish fictional boozer, this was a sobering experience.

He wasn’t alone in falling down. Chris Smalling, Victor Lindelof and Ashley Young provided as much cover as a Sports Direct brolly dancing in a hurricane.

Paul Pogba, the £89m World Cup winner from France, again went missing on an evening he was bought for while the rest, including a profligate Marcus Rashford, looked browbeaten men and kids before the half-hour mark. It was both a chasing and a chastening experience.

So much for all the swotting up beforehand. De Gea had apparently embarked upon “super special” preparations with his goalkeeping coach in how to deal with Messi’s threat. One suspects that didn’t include failing to cope with a 20-yard trundler from the pesky little Barca captain.

Rashford had blown two obvious chances to restore parity at 1-1 on aggregate while Scott McTominay miscontrolled in the home area as United opened up Barca at least three times in a feverish start to the evening. They were misses that did not go unnoticed.

Barca proved as impressive as they were poor at Old Trafford in adding three to the 1-0 win a week ago.

"If we want to get back to Man Utd's true level, true traditions, we have to challenge Barcelona," sad Solskjaer. "They were a couple of levels above over the two games."

United, sixth in the Premier League, were more than a couple of levels behind the hosts. There was a skyscraper of difference in class and technique. United's rebuilding job could take longer than the Sagrada Família if Barca are the benchmark. Reaching Arsenal's level is enough of a challenge.

For once United were not assisted by the magnificent De Gea. For so long a heroic figure at such grounds, one recalls his one-man show against Tottenham at Wembley in January, it is a shame that he chose such an evening to become error-strewn. But when you have defenders who would struggle to mark a bingo card, perhaps we should not be too critical.

De Gea's error sucked the life out of the visiting side to such an extent that one could have sworn United’s pink shirt had began the night red.

Messi had given Fred the slip like Fred Astaire to wallop a brilliant swerving shot beyond De Gea from distance on 16 minutes, but United were still in touch at 2-0 behind overall.

What came next only four minutes later officially signalled the death knell for them when Messi - who has scored 45 goals from 42 games - almost passed the ball towards De Gea from distance only for the Spain goalkeeper to go down in instalments as the ball slipped beyond him and under his grasp.

United were officially done for as the passing, so crisp and calculated in the early forays, became deflated, unconvincing and calamitous. Dare one say it, it almost looked as disjointed and soulless as the ghastly death throes of the Jose Mourinho muddle.

The only benefits to be found was United escaping from the old joint having shed only three.

De Gea also halted an effort from Sergi Roberto before half-time to help prevent a filleting that would not have flattered the Liga leaders.

Shakira singing El Cant del Barca would not have matched Barca fans glee as news then filtered through of Matthijs de Ligt's winner for Ajax.

At least Ronaldo will not be around to halt their side this time, but Barca will also realise this was a phoney war, a match between two traditional superpowers in name only. United simply dissolved under the duress. Next up is likely to be Jurgen Klopp's Liverpool, who carry a 2-0 lead to Porto in their second leg on Wednesday night.

United are firmly back in their box, but Barcelona will not expect Liverpool to be as compliant. They could not manage such a flatlining feat even if they tried.