Germany s Florian Wirtz reacts during the international friendly soccer match between Germany and Belgium in Cologne, Germany, Tuesday March 28, 2023. AP
The four-time world and three-time European champions on Tuesday slumped to a 3-2 home defeat in a friendly against a Belgium team who were dumped out of last year's World Cup in the group stage.
Germany also exited the tournament in Qatar at the first hurdle, for the second straight World Cup, to continue a disastrous four-year spell by their high standards.
"We have lots of work to do. We know that," the manager said after Germany's first loss to Belgium since 1954.
A dominant 2-0 win over Peru on Saturday in Germany's first match since their World Cup debacle had raised hopes of a revival.
But against Belgium, Germany showed they were still well off matching Europe's elite.
"If I was to say that we are super happy, then that would not be true. It's clear that everything isn't at 100 percent," Flick said.
Germany reached at least the semi-finals at six consecutive major tournaments between 2006 and 2016 but have failed to even make the quarters since, having also been knocked out in the last 16 by England at Euro 2020.
Often put down to just bad luck and poor finishing, the poor run of form is looking more and more significant.
After a similar slump which saw Germany knocked out in the group stage at Euro 2000 and Euro 2004, a young team restored confidence by reaching the World Cup last four on home soil in 2006.
But Flick knows an early exit next year as hosts would represent rock bottom for Europe's most decorated national team.
'The worst I've seen'
Not known for mincing his words, Ballon d'Or winner turned TV pundit Lothar Matthaeus laid into the side's timid opening against Belgium, which saw the visitors score twice in the first 10 minutes.
"That was the worst that I have seen in my long, long life," said the 1990 World Cup winner.
"They let the Belgians stand and play," he added.
Flick intervened after just 30 minutes, bringing on Emre Can, who had started the previous match against Peru, and Germany looked a different side afterwards.
"The manager reacted and then things got better," said striker Niclas Fuellkrug, who scored his sixth goal in six Germany caps from the spot.
Captain Joshua Kimmich said that "from the 30th minute it was definitely better", adding "the second half was more like how we imagined it".
Flick called Can "the aggressive leader we needed" and credited the former Liverpool player for "waking up the team".
"An opening 25 minutes like that must never be repeated."
'We still have time'
With Germany already qualified for the European Championship as the home country, Flick had promised to experiment with team selections in the two friendlies and stood down several first-team regulars including Thomas Mueller, Leroy Sane, Niklas Suele and Antonio Ruediger.
The loss however could not be chalked up to blooding inexperienced youngsters, with only four of the 17 who took the pitch on Tuesday aged under 27.
Flick's next test will come in June, when Germany take on Ukraine at home and Robert Lewandowski's Poland away.
"Our goal is to develop further," Flick said. "Games like this are good for our development. We have to take the positive things with us and work on the other things."
The loss to Belgium, who have spent much of the last few years as the world's number one-ranked nation, is a far cry from the lows of a 6-0 thrashing by Spain in November 2020 and the home defeat against North Macedonia in 2022 World Cup qualifying.
But captain Kimmich knows a lot has to change in the next 15 months, saying: "Today we noticed that we are not yet at the top international level.
"Fortunately, we still have a little bit of time."
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