Manchester - Manchester United's powers of recovery carried them to a first Champions League quarter-final in five years but even Ole Gunnar Solskjaer admits beating Barcelona in the Camp Nou is maybe one mountain too many to climb.
Unlike their experience in losing the first leg of their last-16 tie on home soil 2-0 to Paris Saint-Germain, United were not outclassed by the Catalan giants in a 1-0 defeat on Wednesday.
However, on a night when Lionel Messi was left bloodied by a charging Chris Smalling and had little impact after playing his part in creating Luke Shaw's 12th-minute own goal, Barca were still comfortable winners.
"Messi received a black eye and a bloodied nose but Manchester United did not lay a glove on Barcelona," was the verdict of the Daily Telegraph.
Implausibly, Solskjaer's men turned the PSG tie around with a famous 3-1 victory in Paris, but the task of overturning a home defeat against a side of serial Champions League winners is an even tougher one.
"It will be a greater achievement winning that one with the history of Barcelona," said Solskjaer. "They are not used to losing at home."
The scale of the task is shown by the fact that Barca have not lost a Champions League game at Camp Nou since 2013, racking up 27 wins and three draws in 30 matches since.
That is a home European record that the Red Devils can only envy.
Solskjaer famously won the Champions League for United as a player at Barca's Camp Nou against Bayern Munich in 1999.
But he also played a part in a less-heralded moment of the club's history, a first-ever home defeat in European football, at the hands of Fenerbahce in 1996.
Fortress Old Trafford breached
Fortress Old Trafford provided the launchpad for Alex Ferguson's sides to regularly compete for Champions League glory.
However, those days seem long gone. Barca, without ever needing to approach their best, became the fourth visiting side in the past six Champions League games to come away from Manchester victorious.
United's only win in that run was a turgid 1-0 victory over Swiss champions Young Boys in November. That match also contained their only goal in five Champions League games at Old Trafford this season, scored by Marouane Fellaini, who Solskjaer was happy to let leave the club in January.
Against Barcelona, the hosts did not even manage a single shot on target in a Champions League game for the first time since 2005.
"Those statistics are not bright are they?" Solskjaer admitted. "We cannot defend that, not scoring goals at home."
Defeat was a fourth in five games for Solskjaer since the remarkable fightback in Paris.
That win helped land him the job on a permanent basis last month after a brilliant caretaker spell in charge, but as his immediate impact begins to wear off, familiar failings have begun to appear.
The Norwegian boss was reluctant to single out his strikers, citing a lack of creativity.
"We have to provide a bit more ammunition for them and chances for them," he said.
Solskjaer called on Paul Pogba to "run the game" ahead of Barca's visit but instead it was 22-year-old Scott McTominay he praised afterwards for wrestling back control of the midfield after a poor start.
Romelu Lukaku was ineffective up front before being replaced 22 minutes from time, while Ashley Young's wretched display at right-back showed a rebuilding job is also needed at the other end of the pitch.
Solskjaer's early success allowed United fans to dream and, after Paris, they will believe anything is possible in Barcelona.
However, it has also merely papered over cracks that need more permanent solutions come the summer transfer market.