Barca broke their club record by winning the first seven games of a La Liga season.
"We did not control the game in the first half," he told Sport. "We had many inaccurate passes and lost many balls. The second half was all ours and we solved it well with a goal from Adriano.
"We played well for one half and reasonably the other and we have to aim for consistency because the idea is to control it for 90 minutes.
"We were also lacking in movement to keep the ball and give options to the player who has it."
Barcelona's next game is against Celtic in the Champions League.