BARCELONA — Osasuna shattered La Liga leader Barcelona's perfect start to the season with an emphatic 4-2 victory on Saturday, and its coach Hansi Flick said he would take the blame.

The Catalans won all seven of their opening fixtures, but Flick's heavily rotated side came badly undone in Pamplona as Ante Budimir scored a brace either side of Bryan Zaragoza's strike.

Pau Victor had given Barca a lifeline to pull it back into the game before Budimir bagged his second from the penalty spot.

Abel Bretones added a sensational fourth from the edge of the box, before Lamine Yamal pulled one back with a fine effort of his own.

Victory would have matched Barcelona's best ever start to a league campaign with eight consecutive wins, but it was not able to build on its four-point lead over second-placed Real Madrid.

The Spanish champion was set to play third-placed Atletico Madrid in a derby clash on Sunday.

"In the first half we made a lot of mistakes, it's not normal that we play like this — we had a lot of changes in the team, and this is maybe one reason for that," Flick told reporters.

"I think it was necessary. We had so many matches, a lot of players had so many minutes, I have to be careful of that. This is my responsibility.

"If you want to blame someone for this defeat then blame me."

Ahead of a Champions League match against Young Boys on Tuesday, Flick felt he had to shuffle his pack, especially after Barca lost at Monaco in its European opener.

The coach, missing several key players through injury, handed starts to inexperienced defenders Gerard Martin and Sergi Dominguez, as well as Pablo Torre in midfield and Victor in attack.

The coach rested Spain's Euro 2024 starlet Yamal and Brazilian winger Raphinha, among other team regulars.

As a result, Barcelona failed to ignite in the first half and Osasuna winger Zaragoza took center stage.

Last season Zaragoza struck twice while playing for Granada in a 2-2 draw against Barca, a performance which helped earn him a move to Bayern Munich.

On loan from the German giant, Zaragoza created the opener for target man Budimir in the 18th minute, with a fine cross that the Croatian nodded home with ease after escaping the attentions of Dominguez.

Zaragoza finished the second himself 10 minutes later, after being sent through on goal, with the winger bypassing goalkeeper Inaki Pena with a fine ball roll, before slotting into the empty net.

Barcelona complained that there had been a foul on Victor in the build-up, but the referee waved its complaints away.

The leader created little itself, with the best opening falling to Ferran Torres. However, the Spain winger miscontrolled the ball on the edge of the box and was quickly swallowed up by the Osasuna defense.

End-to-end

Victor pulled Barcelona back into the game after Osasuna goalkeeper Sergio Herrera gave the ball away with a poor throw and then could not keep out his early shot from distance.

With Yamal and Raphinha thrown into the fray, Barcelona began to threaten more, although top scorer Robert Lewandowski was taken off with 20 minutes remaining after a flat display.

Against the run of play Osasuna increased its lead.

Dominguez scythed down Budimir in the area as he went to shoot and the striker buried the resultant penalty.

Ruben Pena wasted a glorious chance to grab a fourth, but Bretones made no mistake with a vicious effort from the edge of the box.

Yamal hit back brilliantly from range, and teed up Torres who struck the post, but it was too little, too late.

"It's normal there are rotations, there are a lot of games, it's not an excuse," Barcelona midfielder Pedri told Movistar.

"In the second half we deserved a bit more, but we let in goals when we were at our best."

Osasuna rose to sixth and Zaragoza said his team had been determined to beat the leaders.

"We knew Barca were an incredible team, they have won everything and we knew we had to get stuck into it, and that's how we went out there," explained the winger.

"It's a special game and really nice to play in."

Earlier, Real Sociedad defeated Valencia 3-0 and Getafe won its first game of the season with a 2-0 home victory over Alaves. Rayo Vallecano and Leganes shared a 1-1 draw.

AFP