Barcelona defender Gerard Pique admits they have a problem at the back after defeat to Real Betis.
Betis left the Nou Camp with a 4-3 win on Sunday.
Pique said, "For many years we did not concede as many goals, we know the problem we have.
"They have generated many chances where we have had to defend better.
"We're conceding goals, but also scoring many - one leads to the other."