Barcelona manager Xavi has said that his side are "under construction" while Bayern Munich already "have a built team" following Tuesday's European contest between the two sides.
The overall statistics favoured Barcelona at Allianz Arena, with the Catalan side having more shots - 18 to Bayern's 13 - and also boasting more possession, enjoying 53% of the ball in Munich.
Both sides had four shots on target, meanwhile, but it was the Bundesliga champions that triumphed 2-0 on the night, with Lucas Hernandez and Leroy Sane scoring early in the second period.
After the match, Xavi said that his side have to 'learn from their mistakes' but insisted that the Catalan outfit are in the early stages of their journey, with a lot of changes occurring over the summer.
"You could say that Bayern already have a built team. We're under construction, only at the beginning of our journey," Xavi told reporters after the European contest.
"You can't be controlling a match then conceding from a corner kick. Or conceding a chance from the middle like the play for the 2-0. We have to learn from our mistakes.
"The difference between us and Bayern is that they don't forgive in front of goal. The result is not a reflection of the entire match. But this is the Champions League. If you miss chances, you will end up paying that. We messed up. This defeat is a step backwards.
"We had six or seven clear chances to score. The first half was ours. We did enough not only to draw, but we should have won. We should learn from our mistakes and keep working hard.
"Our marking in the corner was very bad, and we should have fouled the runner in the play for the second goal. They stop the game and we don't. That is what competing means.
"I'm mad because we should have won. We played a match to win. [Robert] Lewandowski missed chances, Pedri got two, Raphinha from outside the box... this is disappointing and unfair.
"Competing means winning corners, closing transitions, or having a chance in front of the goalkeeper and scoring it. I'm leaving angry. We had to win today. We have to be more effective in both of the areas."
Barcelona had a penalty appeal late in the first half when Ousmane Dembele was challenged by Alphonso Davies inside the Bayern box, but the play continued, and Xavi was not prepared to comment on the performance of the referee after the match.
"I didn't see the Dembele foul, but everyone is telling me it was a penalty. Regardless, I don't want to comment on referees," he added.
Barcelona will be bidding to return to winning ways when they resume their La Liga campaign against Elche on Saturday afternoon.