Barcelona secured a much-needed 2-1 home victory over Villarreal in La Liga on Tuesday, racing into a two-goal lead inside 15 minutes before hanging on after Santi Cazorla halved the deficit on the stroke of halftime.
The victory takes Barcelona up to fourth with 10 points after six games, one point behind surprise leaders Granada, Athletic Bilbao, who visit Leganes on Wednesday, and Real Madrid ahead of their game at home to Osasuna the same night.
Barca's win was marred by the sight of Lionel Messi, making his first start this season, receiving lengthy treatment before being replaced at halftime by Ousmane Dembele in what coach Ernesto Valverde insisted was a precautionary measure.
"He noticed a little bit of an issue with his adductor and we preferred for him not to stay on the pitch, but it was just a precaution," he said. "I don't think it's any more than just a niggle but we'll need to wait for tomorrow to confirm."
"We are playing well at home, but I think with the injury to Leo everyone was stopped in their tracks a little bit. I think we're very much on the right track at home, though."
Antoine Griezmann headed Barcelona in front after six minutes, darting in at the near post to meet a Messi corner.
Brazilian Arthur doubled the lead with a spectacular strike from distance as it appeared the Catalans would put their recent troubles away from home behind them, having lost to promoted Granada at the weekend.
It was the first time Messi, Griezmann and Luis Suarez had started a competitive game together for the club and the initial signs were promising.
However, Barca's tempo dropped when Messi had to leave the field for treatment on the half-hour and they were perhaps distracted by their talisman's injury problem when they were pegged back just before the interval.
Cazorla's long-range effort left home keeper Marc-Andre ter Stegen red-faced as he misjudged the swerving shot to allow the visitors back into the game, and anxiety inside the Camp Nou grew when Messi did not emerge for the restart.
Ter Stegen then made amends soon after as he turned away another Cazorla effort, before smartly rushing out of his goal to prevent Samuel Chukwueze from racing onto a through ball.
Barca's new starlet Ansu Fati was introduced for Suarez after 76 minutes, giving Barca a much-needed shot in the arm, firing narrowly wide before seeing strong claims for a penalty turned down in the closing stages as they saw out the win.