Bayern Munich president Franz Beckenbauer on Friday regretted the departure of Brazilian captain Lucio, saying the German club's defence was a cause for concern.
"It's important that the defence sorts itself out. The problem is the defence and I hope that (coach) Louis van Gaal will find the solution," Beckenbauer said.
"The triangle that the goalkeeper and central defenders form must perform better and if not, we will have problems in the Bundesliga."
According to Beckenbauer, the defence has been particularly hit by the transfer of Worl Cup winner Lucio to Inter Milan.
"With hindsight, the decision to let Lucio go was perhaps a mistake," he said. "We're currently missing a player like him who has been the spine of our defence."
Before the fifth game of the season on Saturday, when Bayern play away at Dortmund, the Munich side sit in eighth place on five points.