Pedri and Ferran Torres' late strikes earned La Liga champions Barcelona a 2-0 win over Cadiz in their first competitive home game away from Camp Nou on Sunday.
Atletico Madrid drew 0-0 at Real Betis in a dour clash.
Playing at the Olympic Stadium on the city's Montjuic hill while their stadium is rebuilt and upgraded over the next year-and-a-half, Barcelona were nearly thwarted by visitors Cadiz.
After Getafe held them to a frustrating goalless draw on the opening weekend, Cadiz almost managed the same feat until Ilkay Gundogan cleverly released Pedri to score.
Substitute Torres drove through the middle and tucked home in stoppage time to put gloss on what was another unconvincing performance.
"I'm happy, quite satisfied with the team's work and their positional play too, I think it's a totally deserved victory," said Barca coach Xavi Hernandez.
The Catalan coach, banned from the dugout after being sent off against Getafe, selected 16-year-old Lamine Yamal on the right in place of the suspended Raphinha, also dismissed last weekend as tempers frayed.
Yamal, on his first start for the club, came closest for the Catalans in the first half with an angled strike expertly tipped to safety by Jeremias Ledesma.
The forward thrilled nearly 40,000 fans -- there were around 10,000 empty seats with a low uptake on season tickets because of the temporary move from Camp Nou.
"I think it's very positive for the club and the fans, that 40,000 people came, supporting the team," continued Xavi, despite the relatively quiet atmosphere.
At the other end Barcelona goalkeeper Marc-Andre ter Stegen went one better with a superb save to deny Roger Marti one-on-one, after Alejandro Balde gave the ball away on the halfway line.
New signing Oriol Romeu had a goalbound effort blocked after a scramble in the box early in the second half as Barcelona struggled to break down their Andalucian visitors.
Ruben Alcaraz almost gave the Yellow Submarine the lead but lashed a shot wide, while Chris Ramos also came close with a rasping effort.
Barca midfielder Gavi nodded against the bar at the other end, before Xavi threw on Moroccan winger Ez Abde in his stead.
The coach switched to a three defender system, also bringing on Ansu Fati for Balde as he sought the breakthrough.
Upping the pressure
Barcelona tossed crosses into the area, looking for Robert Lewandowski, but the Polish forward failed to make a nuisance of himself.
"He will score, he needs to have more patience," said Xavi, concerned at Lewandowski drifting from his position to get involved in the play.
"He wants to come, I understand it. You can't lose your positioning.
"I think he was good in the second half working for the team, and he set up the goal for Ferran."
Abde drew a fine save from Ledesma with a vicious curling effort as Barcelona regrouped following a cooling break in the hazy evening heat.
Eventually they found the breakthrough when former Manchester City midfielder Gundogan dinked a cute ball through for Pedri to slide past Ledesma with eight minutes remaining.
The Canary Islander held up a shirt in tribute to Tenerife, currently ravaged by wildfires.
"It was tricky, yes, we should have scored much earlier," Xavi told Movistar.
The coach praised Gundogan for his impact in the final third.
"That's why we signed Gundogan, he makes the difference with the final ball," he added.
Cadiz almost levelled through Darwin Machis but he hammered a strike over the bar from close range.
Torres secured the victory for Barcelona after he ran on to Lewandowski's header, through the middle of Cadiz's crumbling defence and slotted home.
"We suffered again but we won, which was the most important thing to gain confidence," Frenkie de Jong told Movistar.
Diego Simeone's Atletico Madrid could not follow up their opening weekend win with another at Real Betis, who shaded the game.
Isco impressed again in midfield for the hosts, who had more shots but failed to get any on target.
Mario Hermoso forced a save from Rui Silva but neither team created much danger in a disappointing stalemate.