Star striker Robert Lewandowski believes Bayern Munich are suffering from a lack of on-field leadership.

The German champions parted ways with head coach Niko Kovac at the start of the week and lie fifth in the Bundesliga going into a crucial Der Klassiker date with Borussia Dortmund on Saturday.

Hansi Flick has been placed in charge on an interim basis but the dugout is not the only place where Bayern are in need of more defined leaders.

Lewandowski attributes a below-par run of performances to the over-reliance on himself and Manuel Neuer to provide vocal guidance on the pitch, insisting they alone are "not enough".

Experienced figures Rafinha, Franck Ribery, Arjen Robben and Mats Hummels, now of Dortmund, all left the club during the close season, creating a vacuum of authority not filled by more youthful replacements.

"There should be a leader in each area of the team, on each line: goalkeeper, defender, one in the midfield, one in attack," Lewandowski told Suddeutsche Zeitung.

"That would be perfect. It can't be on one player to lead, that's too much, that's impossible.

"What we're sometimes missing are commands.

"The young players are of course a little reserved, or they have a problem with the language. But I know that two or three months in a country are enough to be able to give orders. You have to expect that."

Lewandowski, 31, suspects the reserved nature of the younger players in the squad is the result of a changing society.

"Players today are a bit afraid to talk, or maybe don't have that desire," he said.

"This is a generation that writes a lot of text messages, communicates a lot on the internet, makes fewer phone calls. It's just another culture. 

"Previously you had 20 players in the dressing room, everyone said something, often loud, and the next day it was okay again to talk."

But the centre-forward's fears about the next generation are not shared by team-mate Javi Martinez, who feels one future captain has already emerged.

The versatile Spaniard is adamant Germany international Joshua Kimmich, an ever-present member of the starting XI, will prove a strong long-term successor to captain Neuer.

"He's a player that fits perfectly with Bayern," Martinez wrote in a column for sports magazine Socrates. "He's internalised all the values of the club from an early age. It feels like he's already made 1000 games for the club.

"That's why I'm convinced he'll play for many, many years and one day lead the team."