David Villa's goal just after half-time was enough to see off Sporting Gijon as Barcelona lumbered through another lethargic display in front of their home fans to win 1-0.
The Catalans lost their home opener 2-0 to newly-promoted Hercules last time out at the Nou Camp and failed to inspire again against a second-string Sporting side.
Away manager Manolo Preciado made eight changes and while Barcelona were without their star man Lionel Messi they would have expected a far easier evening when the team sheets were announced.
Sporting's fringe players proved, however, a resilient match for Barcelona who dominated possession but had to rely on Villa's 49th-minute strike after Dani Alves' through-ball gave him a rare sight of goal.
Barcelona were without Messi after he suffered an ankle injury following a Tomas Ujfalusi tackle in the weekend win over Atletico Madrid and in his absence only offered rare glimpses of their class.
It was defender Gabriel Milito who highlighted the opening period when his superb long-range pass picked out an unmarked Andres Iniesta. The World Cup winner took a touch before driving in a low and hard shot that Ivan Cuellar saved well.
It was a rare clear opening for Barcelona as Sporting's rearguard frustrated them.
Villa, playing against his home-town club, scuffed the ball wide when given a sniff of space while Bojan Krkic's solo run was closed out by the back-tracking defence.
At the break home boss Pep Guardiola brought on Gerard Pique and Pedro, who along with Messi had been the players to drop out from the Atletico win.
Guardiola's changes worked in so far as a goal arrived four minutes later when Alves' through-ball sent Villa into space and the Spain striker did not pass up his first real opportunity with a cool finish that beat Cuellar at the near post.
It was Barcelona's first home league goal of the season, but it failed to break the away side's resolve as they were kept in touch by the hosts' malaise.
Sporting were hardly a threat themselves but Milito had to act quickly to shepherd out David Barral when he bore down on goal before Barcelona had to withstand a small period of pressure late on to collect the points.