Barcelona manager Ernesto Valverde has admitted he is concerned about his side's form after the Catalan outfit came from behind to beat Real Sociedad on Saturday.
The Spanish champions are now outright top of the league after Real Madrid dropped points in their 1-1 draw with Athletic Bilbao, but Valverde acknowledged there is still room for improvement in spite of their current standing in Spain's top flight.
"I'm a little worried, a little, but very little," Valverde said in his post-match press conference, as quoted by Marca. "There are things to improve, of course.
"They pushed us up, and every time we went long we won the ball, but we got into trouble because we gave them the initiative."
Aritz Elustondo put the home side in front before Barcelona hit back quickly in the second half, with Luis Suarez and Ousmane Dembele netting to secure all three points for Valverde's side
"The atmosphere is spectacular, people were very motivated," the former Valencia boss continued. "When they finish the rostrum behind the other goal, it's going to be even harder to play here."
Arturo Vidal, Barcelona's main summer signing, was given a 15 minute cameo towards the end of the match and Valverde said he brought the former Juventus and Bayern Munich midfielder on to sure things up.
He added: "There were 15 minutes left and Arturo is a player who reinforces us in the midfield."
Barcelona's next match is a Champions League tie against Dutch side PSV at Camp Nou as they look to improve upon last season's performance in Europe's elite club competition.