Neymar celebrates after sparking the rout with his first goal in La Liga.
Neymar scored his first Primera Division goal while Lionel Messi continued his red-hot form as Barcelona brushed aside Real Sociedad 4-1 to make it six league wins from six at the start of the season.
Sociedad hit the crossbar in the first minute but Barca then scored three times in quick succession to all but end the match before half-an-hour at the Nou Camp.
Summer signing Neymar, whose only previous goal for Barca was in the Spanish Supercopa against Atletico Madrid, opened the scoring in the fifth minute, Messi doubled the lead three minutes later and Sergio Busquets made it 3-0 in the 23rd minute.
Sociedad pulled a second-half goal back through Alberto De la Bella and briefly threatened to make further inroads, but they could not find another breakthrough and Barca wrapped up the scoring through substitute Marc Bartra with 13 minutes left.
The win leaves Barca on 18 points from six games, but it might have been a different story had Haris Seferovic’s thunderous early shot from the edge of the box found the top corner of the net rather than the smashing against the bar.
Marc Bartra celebrates after scoring the final goal in Barcelona’s 4-1 win.
Victor Valdes would have had no chance had that been a couple of inches lower, but Barca wasted no time in capitalising on that escape as Neymar took advantage of a mix-up in the visiting defence to put the champions ahead.
Alexis Sanchez’s cross from the right should have been cut out but Sociedad goalkeeper Claudio Bravo and Liassine Cadamuro seemed to expect the other to deal with it, and Neymar running in behind them had the simple task of tapping home from four yards out.
Neymar then turned provider as Barca made it 2-0, the Brazilian making a good run down the left before dinking a cross to the far post where Messi planted a diving header past Bravo.
That was Messi’s 10th goal of the season in all competitions and he should really have made it 11, 15 minutes later as he contrived to hit the underside of the bar from point-blank range having just seen his audacious back-heel saved by Bravo.
Barca need not have worried though as Sociedad made a complete hash of trying to clear the danger and Busquets made them pay by intercepting a pass just outside the box and driving a low left-footed shot past Bravo.
There was no way back for Sociedad after that, and Barca might easily have added further goals at the start of the second half with Bravo being called on to deny Messi twice and also Neymar.
Sociedad, who finished fourth last season, gave themselves a glimmer of hope when De la Bella pulled a goal back from close range in the 63rd minute and then Antoine Griezmann twice tested Valdes as the visitors enjoyed a purple patch.
Barca never looked like surrendering their lead though and they wrapped up the points when Bartra made it 4-1 following a pass by Messi.
A first-half brace from Diego Costa was enough to help Atletico keep the pace with Barcelona
Atletico Madrid also maintained their 100% record to start the season with a 2-1 win over Osasuna.
A first-half brace from Diego Costa was enough to help Atletico keep the pace with Barcelona at the top of the La Liga standings.
Costa’s opening goal came from inside the penalty area and it didn’t take long for the 24-year-old to double his side’s advantage as he latched onto Jorge Koke’s cross with a powerful header in the 25th minute.
In between Costa’s goals Arda Turan had found time to head narrowly wide and while Atletico had now begun to move through the gears their progress was slowed by Oriel Riera’s strike on 43 minutes to pull one back for Osasuna.
Mario Suarez was fouled Abella Damia and from the resulting free-kick Armenteros picked out Riera to score from six yards.
Costa was denied his hat-trick shortly after half-time when Osasuna goalkeeper Andres Fernandez parried his shot while Armenteros could only muster a weak effort at the other end.
Damia wasted Osasuna’s best chance when he shot over from close range and from there Atletico could have grabbed a third with Turan missing the target and Emiliano Insua twice going close.
Malaga moved into the top half of the table with a 2-0 win over lowly Almeria at the La Rosaleda.
The visitors missed a chance to break out of the relegation zone, but showed signs of promise as they held Malaga to a 0-0 draw at the break.
Fernando Tissone and Francisco Portillo were on target as Malaga made it four games without defeat after their sluggish start to the season.
Duda provided the corner and when Sergio Sanchez headed across the box, Tissone was on hand to provide the finishing touch in the 69th minute to put Malaga in front.
Roque Santa Cruz was brought on as a late substitute and he provided the pass for Portillo to curl one home and seal the win.
Levante were left frustrated after being held to a 1-1 draw by ten-man Real Valladolid in their mid-table clash at Estadi Ciutat de Valencia.
A bad-tempered match saw one red and five yellow cards with Valladolid’s French left-back Zakarya Bergdich given his marching orders in the 44th minute with the score at 1-1.
But Levante were unable to capitalise on playing half the match with an extra man with Andreas Ivanschitz failing to convert a match-winning penalty after Bergdich had gone.