Germany didn't play the way it usually plays. Coach Joachim Loew isn't sure why.
Stymied by Mexico's skillful forwards and speedy counterattacks, the defending World Cup champions played a sloppy first half, gave up too many chances and ultimately conceded a goal that held up in Mexico's 1-0 victory on Sunday, 17 June.
"We looked nervous and we were not able to play the way we wanted to play," Loew said. "We will have to analyse why that was the case."
Germany is now in an unfamiliar position. The squad had not lost a World Cup opener since 1982 and won its four previous initial matches by a combined score of 20-2.
For a defending World Cup champion, however, the situation is more common. Three of the past four have failed to make it out of the group stage.
Reminded of that statistic, Loew offered a guarantee.
"We will not suffer that fate," he said. "We will make it to the next round."
Germany's path through Group F includes a match against Sweden next on 23 June, and it then faces South Korea on 27 June.
"As far as the psychological situation, everyone is unhappy, crestfallen," Loew said. "We have to look forward. We have to put this behind us. Our team certainly has experience dealing with losses, and the next match will be decisive for us. We have to win it. It goes without saying."
Although they breezed through qualifying, the Germans had enough questionable results in recent friendlies to put fans on edge, and Loew was questioned for leaving 22-year-old Manchester City winger Leroy Sane out of his squad.
The coach instead opted for another 22-year-old attacker, Julian Brandt, who entered late in Sunday's match and blasted a shot just wide of the Mexican goal about two minutes later that had Loew covering his face with his hands.
Germany defeated Mexico 4-1 in last year's Confederations Cup while sporting a younger lineup.
"I believe we have a relatively young team here. The average age isn't too high," Loew said. "Last year at the Confederations Cup, it was a completely different situation. You can't compare the two."
In the second half on Sunday, Loew at least saw some more characteristic play out of his team, which kept the ball in the Mexican end for long stretches. But he also saw some skittishness under pressure.
"We had a couple of shots on goal, but somehow it seemed jinxed," Loew said. "The ball didn't go in the goal, and sometimes they were a bit too quick in finishing, did not take their time, did not keep their cool."
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