Two things killed the atmosphere on Saturday. The 3-0 midweek defeat by Roma stunned Barça, but it was the fourth successive year in which they’d exited at the last-eight stage and they’ve lost four and drawn one of their past five European quarter-final away ties, scoring one and conceding 13.

The second reason was the rain. Camp Nou is three quarters uncovered and while the downpour did wonders for those selling umbrellas and waterproof ponchos outside Europe’s biggest stadium, the weather knocked 15,000 off the attendance. The crowd reached a still-impressive 69,544, but there were 30,000 empty seats.

Amid their soul-searching and the opinion formed in hindsight that Barça are finally now missing Neymar, the Catalans must continue to get over another European disappointment.

They play Saturday’s Copa del Rey final against another vanquished Champions League last-eight team, Sevilla. Off the field, Barça last week confirmed their plans to start rebuilding Camp Nou in 2019, raising the capacity to 105,000 and providing cover for all. Given the woeful last winter in western Europe, it couldn’t be more timely.

The shabby stadium needs it and Chelsea were justified last week in their complaints to Uefa, citing aggressive policing, incompetent stewarding and “generally unsafe conditions”. They could have added excessive ticket prices to their litany.

Camp Nou hasn’t had a serious upgrade since the Spain World Cup in 1982 and while travelling English football fans are seldom angels, there is definite room for improvement in the policing at Spanish football matches.

Barça are in the market for more top players such as Antoine Greizmann, but need to watch their salary to revenue ratio, especially with the stadium development in the offing. They’ve planned for the departure of the mesmeric Andres Iniesta – most likely to China – by buying Coutinho and their new boss Ernesto Valverde has been a success, calming things down against a backdrop of fans wanting the president out at the start of the season and ongoing demands for Catalan independence.

There are songs and flags for independence, liberty or freedom for Catalan political prisoners at every Barça home game. On Saturday, a large flag was unfurled and applauded in memory of Guillem Agullo, a Catalan independent from Valencia murdered 25 years ago. Football and politics is fused at every Barça game, but the players usually steer well clear of talking politics when they speak to the media and even those with pro-independence sentiments have quietened, knowing how divisive the issue can be.

Valencia played their part in an excellent game. Before Saturday’s defeat Los Che had won eight and drawn one of their previous games. The team who sit fourth in Spain’s all-time league table had finished 12th in each of the previous seasons – a disaster by their standards. They went into Saturday’s game third and above Real Madrid, marking a vast turnaround for the club where Singaporean Peter Lim is the majority shareholder.

Their squad is stacked with talented youngsters, from the 21-year-old Portuguese winger Gonçalo Guedes, on loan from Paris St Germain, to Brazilian striker Rodrigo Moreno and locally born midfielder Carlos Soler. Valencia’s youth system is one of Spain’s best and they continue to produce full-backs, but they make effective use of the loan system too.

Andreas Pereira is another of their loan players who arrived for a season from Manchester United.

“There’s an incredible team spirit here,” said the 22-year-old Brazilian who was born and raised in Belgium. “We don’t only train together but eat out together. We play very good football with an explosive counter attack. The manager demands this and pays incredible attention to detail. If something goes wrong then he tells you. I lost the ball in one game and was thinking ‘Damn! I’ve lost the ball,’ but the manager doesn’t want me to think, he wants me to press immediately, to focus without hesitation.”

Pereira picks out midfielder Geoffrey Kondogbia, 25, as the star of a very good side.

“He’s played almost every game, even through injury and is always consistent and powerful,” he said.

“I’m surprised that we’ve kept such a high level all season, but I knew we were at a high level when we were disappointed only to draw with Barcelona at home. Everyone would have expected Barça to smash us last season.”

After not being included in any of United’s first three match squads, Pereira went to Valencia to play football and has racked up 1,300 minutes of first team action so far this season.

“I’m a better player now,” he states. “I’m used to playing for a high level team that expects to win, to be competing at this level. I’m mentally tougher too, especially after my thigh injury, where I had set backs. I’ve never been injured before and was impatient to play again, but I had to be patient and not rush. I was just frustrated as I was playing very well before injury.”

Pereira came on for the last 23 minutes in Camp Nou and did well.

“I felt that was my proper comeback,” he said. “And now I’m ready for the rest of the season, to confirm our place in the Champions League which is a superb achievement.”

But will he be around in Spain to play in the Champions League next season?

“Valencia approached my agent and said they want to buy me which is flattering, but it wasn’t like it was reported in the media,” he explains. “People said I’d demanded talks with Jose Mourinho when I’ve demanded nothing. The Valencia coach speaks with me a lot and we have a good understanding, but as far as I’m concerned I’m still a Manchester United player, with a contract at Old Trafford until 2020 and an ambition to make it at United. I’ve never sought to leave United.”

Nor have United sought to sell him, but they will benefit from a better player when – or if – he returns to Manchester.