Germany's defensive line is a cause of concern ahead of the World Cup in Russia, according to Jurgen Kohler.
Joachim Low's side are backed among the favourites to retain the title secured in Brazil four years ago, although the world champions have lost seasoned campaigners at the back.
Philipp Lahm and Per Mertesacker have both retired since glory in 2014, with Bayern Munich duo Jerome Boateng and Mats Hummels now the more experienced players of Low's defensive ranks, but Kohler is not convinced.
"I simply miss the consistency. If central defence does not play at the highest level, it will be difficult for any team," the 1990 World Cup winner told T-Online.
"I have the impression that many players are no longer used to leading duels.
"Especially when opening up in the back of the defence, the team has a large deficit."
Germany's World Cup defence begins against Mexico on Sunday, before facing Sweden and South Korea in Group F.
Despite Kohler's concerns about the squad, the former Borussia Dortmund man has backed Low to get any issues under control.
He added: "I believe that Jogi Low has proven in recent years that he can make a team fit to the point."
