Germany defender Mats Hummels said the team went "wild" in the second half against South Korea, losing their discipline as they tried in vain to find a goal that would have kept them in the World Cup.
For the first time in their World Cup history, Germany were eliminated in the group stage following their 2-0 defeat to South Korea.
The game was goalless until stoppage time, and after Sweden took a sizable lead over Mexico in the simultaneous group game, Germany knew only a win would put them through to the knockout stage.
But Hummels admitted a bit of panic set in as Germany pushed for but could not find a winner.
"We were wild after the 65th minute, left our positions, ran into counters, lost our structure," he told German broadcaster ARD. "If I had scored that goal in the 86th, we'd all be happy now. But now it's just a bitter, bitter evening for us."
Hummels had a chance to be the savior three minutes from time but his free header from inside the area bounced over the bar, and South Korea went on to score twice as Germany abandoned their defence in pursuit of a win.
"It's hard to put in words. We believed in ourselves until the end," Hummels said. "Even after the 1-0, we tried to turn it around. We did not get that ball across the line. I should have scored in the 86th minute. It broke our neck that we did not convert our chances."
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Germany ended up finishing bottom of the group after their opening defeat to Mexico, with their only three points coming in the dramatic late win against Sweden last week.
Asked what happened in the four years since Germany demolished the previous World Cup hosts Brazil 7-1 in the 2014 semifinals and went on to lift the trophy, Hummels credited the improved defence of their opponents.
"The smaller teams have learned how to defend," Hummels said. "Every team has had its problems. And we manoeuvred ourselves into that position against Mexico. How South Korea score, it's just like that."
The World Cup exit capped a difficult lead-up to the tournament that saw Germany draw friendlies with England, France and Spain, then lose to Brazil and Austria, and only squeeze past Saudi Arabia 2-1.
"We have several points we now must address," Hummels said. "Our last convincing match, that was back in autumn of 2017."
Germany coach Joachim Low said "I bear the responsibility for the exit" and admitted his team's performance did not warrant a spot in the knockout stage.
"The disappointment of being eliminated is just huge," Low said. "We didn't deserve to win the title again, we didn't deserve to get into the last 16. We wanted to win but we didn't have what it takes, we lacked the fluency, the ease of play.
"We knew that Sweden were leading but we didn't have enough to get a goal. We deserved to be eliminated.""
Before the tournament, Low signed a contract extension through to 2022, and he said he would take some time to consider his future.
"This is hard to say at this point, it'll take a couple of hours," Low said when asked if he would be staying on. "I'm shocked that we didn't manage to pull it off. I really had the feeling that the team, they really wanted to go forward. I'm incredibly disappointed by this elimination but I will think about it calmly."
Before the game, German Football Association president Reinhard Grindel said coach Joachim Low's job was safe regardless of the result, and general manager Oliver Bierhoff said he expected Low to stay on in his current role.
"It's just very frustrating and a big disappointment," Bierhoff said. "In the end, it was not enough. We must accept it. Now is not the time to go into the analysis of what went wrong. I strongly believe that Jogi will continue."