Germany need to be successful again “very quickly” after their group-stage exit from the World Cup in the summer, says former defender Per Mertesacker.
Defeats by South Korea and Mexico meant the 2014 winners failed to progress past the opening round of a World Cup for the first time since 1938.
Joachim Low remains their manager.
“We can start to think about what we have done wrong and where our reputation has gone to a very negative energy,” Mertesacker told the BBC.
The 2014 World Cup winner, speaking on the Euro Leagues Football Show before Saturday’s 3-0 Nations League defeat by the Netherlands, said Low needs improvements quickly if he is to avoid a “very difficult situation”.
But the former Arsenal defender, who retired in the summer, said there could be a “nice process” of change after they “struggled being champions”.
“Very quickly you need to be successful,” he said. “They have changed a few players and a few staff were removed, but in terms of the big figures, they have stayed in their jobs.”
Mertesacker, who played 104 times for his country, said people “took it for granted” they always reached the knockout stages of major tournaments.
“We always found a way to cope with adversity,” he said. “We were reliable with producing when it counted. This time it was a strange feeling to see them struggle.”
Germany, who have won only three of their past 12 matches, face France in the Nations League on Tuesday.
Mertesacker on Ozil’s ‘sad’ retirement
Mertesacker acknowledged “there is always someone to blame” after a team fails to perform at a World Cup, but said it was “sad” to see former team-mate Mesut Ozil quit international football in July.
The 29-year-old Arsenal midfielder was criticised after being photographed with Turkish president Recep Tayyip Erdogan, and said he received hate mail and was blamed for Germany’s performance in Russia.
Ozil, a third-generation Turkish-German, was born in Gelsenkirchen and was a key member of his country’s 2014 World Cup-winning side.
“I am German when we win, but I am an immigrant when we lose,” he said when he announced his international retirement.
Germany’s football association “emphatically rejected” Ozil’s allegation of racism, but said it could have done more to protect him from abuse.
Mertesacker said “no-one did a good job” dealing with the situation.
“Some players decided to retire in their own fashion,” said Mertesacker. “In Mesut’s case, it wasn’t possible.
“I feel sad about the football association and Mesut and that they didn’t find a way to go out on good terms.
“Who is the next Mesut Ozil? Who can step up and take us up to the Frances of this world, who overtook us when we were feeling complacent?”
Mertesacker on young English players
Mertesacker, 34, became Arsenal’s academy manager in the summer – and he hopes he can help more young English players break through in the Premier League.
But he says some will have to take risks – including moving abroad to develop themselves.
Borussia Dortmund’s Jadon Sancho, who made his England debut on Friday, is one of a number of English youngsters playing in Germany’s Bundesliga.
“We are finding the talent, but how can we make them cope with the league and cope with all of the money and madness that comes in?” said Mertesacker.
“We have to get rid of the feeling that we have everything in England and we don’t need to assess other countries. It is just wrong. Sometimes we can send them away from home, and away from their comfort zone.
“I am now responsible for giving them the right ingredients so they can cope with that and can cope with going away.”
Mertesacker on new ‘challenge’ at Arsenal
As well as developing Arsenal’s academy, Mertesacker wants to form a relationship with new first-team manager Unai Emery that means they can “be honest with each other”.
Mertesacker was Gunners captain for two years under Arsene Wenger but says he “likes the challenge of new people who treat you different”.
“The easiest way for me would have been if Arsene had stayed,” he said. “He would have trusted me and given me an easy way. But I am excited about the new stuff and the change in management.
“Unai Emery is a hard coach and is totally focused on what happens on the grass. That is his main focus – to get us back in the Champions League.
“It is exciting that I am part of that process. People want to see results but we need to make sure the change happens in the right way and not to rush it too much.”
Mertesacker on Cech – and what Arsenal can learn from him
One player who Mertesacker thinks can provide valuable experience and knowledge is goalkeeper Petr Cech.
The 36-year-old former Chelsea player has won the Premier League four times, which – as Mertesacker pointed out – “not a lot of the current Arsenal squad could say”.
Cech has previously questioned Arsenal’s mentality, claiming the need to play stylish football had been more important than victory.
“Cech’s background at Chelsea, that is the way he won,” said Mertesacker. “You can feel when we went there it was always tough and we struggled to deal with the intensity and that defensive ruthlessness.
“We can take that on. We have to learn and adapt to what Chelsea have brought.”
Mertesacker added Arsenal are starting to get rid of the “nice way”, and are winning despite not playing particularly well.
Since opening the season with back-to-back defeats, the Gunners have won nine matches in a row and are fourth in the Premier League.