MADRID (AFP) - Pedro Rodriguez scored a hat-trick as Barcelona maintained their 100 per cent start to the La Liga season with a comfortable 4-0 win over Rayo Vallecano on Saturday.

The Spanish international rewarded the visitors' bright start when he slotted from after some brilliant play by Lionel Messi on the half hour mark.

However, just as in recent weeks, Barca were thankful to goalkeeper Victor Valdes for keeping them in front as he saved his second penalty in as many games when he palmed away Roberto Trashorras' effort 10 minutes before half-time.

That was to be the turning point as Pedro added a second barely two minutes into the second-half before sealing his hat-trick 13 minutes from time.

Cesc Fabregas rounded off a fine evening for Gerardo Martino's men with a thumping finish two minutes later.

"We know that Vallecas is a difficult place to come. They have a competitive team, but we managed to find the spaces and score the goals," Pedro told Gol TV afterwards.

"I am happy with the overall work of the team. In the personal aspect, obviously I am happy too, but I need to give my thanks to my teammates," he added after receiving a trio of fine assists from Messi, Neymar and Fabregas.

Rayo had conceded 14 goals in their last three games and 12 in their previous two meetings at home to Barca, but they had the first clear chance of the game on three minutes as Johan Mojica's cross was met by the unmarked Alberto Perea and Valdes was forced into a fine save.

Seconds later Barca ought to have taken the lead as a sensational touch by Lionel Messi took him beyond two Rayo defenders on the edge of the area, but he overran the ball as he rounded goalkeeper Ruben Martinez and Anaitz Arbilla cleared.

Neymar then had two great chances to score his first league goal for Barca, but he was denied by a goal-line clearance from Tito and then fired wide following a great turn and pass by Messi.

The visitors did eventually take the lead on 33 minutes thanks to another brilliant piece of play by Messi as he again sucked the Rayo defence in before laying the ball off to Pedro who finished into the far corner.

Rayo were handed a lifeline two minutes later though when Adriano was very harshly punished for a foul on Trashorras, but Valdes continued his sensational form as he parried the midfielder's weak spot-kick to safety.

The hosts were left to rue that missed opportunity when Pedro slid home from Fabregas' cross to put the game to bed within two minutes of the second-half.

Messi twice came close to a third and Neymar struck the post as Barca cut through the Rayo defence at will in the second period and it came as no surprise when the third goal did arrive as Neymar unselfishly teed-up Pedro to seal his hat-trick.

Fabregas sealed the rout 11 minutes from time when Barca's pressing caught Rayo in possession deep inside their own half and Xavi squared for his Spanish international colleague to fire home.

Atletico Madrid also maintained their 100 percent record so far this season as second-half goals from Raul Garcia and Diego Costa handed them a well-deserved 2-0 win away to Valladolid.

Almeria kept up their record of having scored and conceded at least twice in every game since their return to the top-flight with a 2-2 draw at home to Levante.

And Real Sociedad's winless league streak extended to four games as they could only manage a 0-0 draw at home to Malaga.