Seydou Keita scored a hat-trick as Barcelona put their recent indifferent form behind them after thrashing Zaragoza at the Nou Camp.

Zlatan Ibrahimovic bagged a brace and Lionel Messi scored the other as the Catalans swept the visitors aside with a fine display of attacking football reminiscent of their early-season performances and the form which saw them capture the treble of Primera Division, Copa del Rey and Champions League trophies last season.

Pep Guardiola's side had looked a pale shadow of that team in their last three matches.

Barca struggled to beat Almeria in their last home match, could only draw 0-0 at Valencia last weekend and went down 2-1 to Russian side Rubin Kazan in the Champions League on Tuesday night.

The Catalans had also only scored twice in those three matches.

Despite that dip in form, Guardiola insisted before this match that he still had faith in his squad.

And he looked to be right as they began strongly and almost took the lead after five minutes, when Xavi put Messi through but the Argentinian dragged his shot wide.

Ibrahimovic then forced Zaragoza keeper Juan Pablo Carrizo into a fine save as the home side continued to press.

The Argentinian also denied compatriot Messi as that pressure intensified.

But the Catalans had to wait until halfway through the first period for the vital breakthrough as Keita headed home Messi's cross to spark a notable sense of relief in the Nou Camp.

And five minutes later, the Barca fans knew their team were really back to normal as Ibrahimovic smashed home a thunderous free-kick from over 30 yards out to make it 2-0.

Carrizo should have done a lot better with the attempted save, but the home side cared little and they went three up four minutes before the interval, when Keita tapped into the empty net after Ibrahimovic unselfishly squared Xavi's defence-splitting pass.

Keita then returned the favour after 56 minutes, when the African set up Ibrahimovic for a routine finish at the near post as Barca went 4-0 up with over half an hour still remaining.

Jorge Lopez pulled a goal back for Zaragoza with 12 minutes left after Victor Valdes was unable to hold on to the initial shot.

But that was a mere blip for the Catalans and Guardiola's side restored their four-goal lead less than three minutes later, when Andres Iniesta put Messi through and he beat Carrizo with an exquisite lob to make it 5-1.

It was to be Keita's night, though, and the Mali midfielder completed an excellent hat-trick with four minutes remaining when he headed home Iniesta's corner to make it 6-1 and round off a superb night for both himself and the team.

The resounding victory sees Barca move three points clear of Real Madrid at the top of the table after eight rounds of the championship.

Zaragoza, meanwhile, drop to 15th.