Rivaldo was reacting to Barca's 4-4 draw in Montjuic for the first-leg of their Copa del Rey semifinal with Atletico Madrid.
He told Betfair: “Luckily, the team was able to score four goals against Atlético, but conceding four is worrying. Barcelona are playing very well but I don’t remember the last time they conceded four goals in this way.
"Therefore, I think it is necessary that these errors are not repeated in the next matches, which will be decisive for the success of the season.
“Everyone likes football matches with lots of goals, but surely when there are so many it is because there were many defensive errors . A match of this level has the creativity of some of the best players in the world, but a result like this is surprising. Luckily for both teams, it ended in a draw. But what if one team had been more successful defensively? It could have been 4-0 or 4-2.”
For Rivaldo, there is no favourite to reach the final in Seville after the 4-4 draw.
“A game like this, which ended 4-4, shows that everything is still open . For me, both Barcelona and Atlético have a chance of winning and qualifying. In other words, a 50% chance for each of them, even though it will be played now at the Metropolitano. The first leg showed that, that the tie is very even.”