MOSCOW - Winners of the previous World Cup have been finding it hard to get out of the group stage in recent tournaments.
Now Germany is in danger of becoming the newest member of a club no one wants to join.
The 2014 tournament champion and the world's top-ranked national team was exposed defensively and surprisingly beaten by Mexico 1-0 Sunday, putting its hopes of advancement from Group F in doubt.
Well, not everyone is in doubt.
"We will make it," Germany coach Joachim Loew said. "There's no reason to fall apart because you lose one game."
Hirving Lozano scored in the 35th minute, picking up Javier Hernandez's pass inside the penalty area and beating Mesut Ozil before shooting past goalkeeper Manuel Neuer from 10 yards out.
"I don't know if it's the biggest victory in (Mexico's) history, but one of the biggest for sure," said Lozano, a 22-year-old forward. "My teammates and I did some great work. We all ran our hearts out. This is the result of all that hard work."
Three of the previous four reigning World Cup champions - France, Italy and Spain - failed to reach the knockout stages. Two of them lost their opening matches, while the Italians had to settle for a draw.
Germany is bidding to become the first team to repeat since Brazil in 1962, but it has won only one of its past seven games overall. The Germans hadn't lost a World Cup opener since West Germany fell 2-1 to Algeria in 1982.
Mexico had never beaten Germany in a competitive match but was transformed from the team that lost to the Germans in last year's Confederations Cup, conceding twice in the opening eight minutes of the 4-1 defeat.
Lozano got Mexico going with a deflected shot over the bar in the first minute. That set the tone for El Tri to torment Germany on the counterattack, with Lozano taking full advantage of right back Joshua Kimmich's tendency to go forward.
"We were nervous, and we weren't playing the game we wanted to play," Loew said. "We need to see what caused this."
After Lozano's goal, Mexico goalkeeper Guillermo Ochoa pulled off a spectacular save to keep the score even, palming a shot by Toni Kroos onto the crossbar.
With key players tiring in the second half, Mexico pulled back and substituted for Lozano and Carlos Vela. Germany then dominated possession, but when it broke through the Mexican defense, the shooting was poor.
Seeking defensive reinforcement, Mexico coach Juan Carlos Osorio brought on 39-year-old veteran Rafael Marquez to play in his fifth World Cup.
"You had the feeling that the ball just wouldn't go in anyhow," Loew said. "Everyone's very disappointed."
Mexico still has to play South Korea and Sweden, which Osorio called "a tough nut to crack." Germany needs points from matches against Sweden on Saturday and South Korea on June 27 to avoid elimination.
"We're already in the knockout stages," Neuer said, "because we only have finals now."
Switzerland 1, Brazil 1
ROSTOV-ON-DON, Russia - Brazil joined the growing list of accomplished national teams struggling to win their opening matches in Russia.
Philippe Coutinho gave Brazil, a five-time World Cup champion, the lead in the 20th minute with a volley that bounced in off the right post. Switzerland's Steven Zuber headed in the tying goal in the 50th, and Mexican referee Cesar Ramos dismissed complaints Zuber had shoved defender Miranda before getting to the corner kick taken by teammate Xherdan Shaqiri.
Ramos also ignored a penalty claim late in the second half when Gabriel Jesus was wrestled to the ground by Switzerland defender Manuel Akanji. Swiss players ended up with three yellow cards in the Group E opener, and 10 of the 14 fouls they committed were on Brazil forward Neymar.
Switzerland dominated the midfield for long spells against a Brazil team that lost its previous World Cup match 7-1 to Germany in the 2014 semifinals.
Besides Brazil and Germany, Argentina was held to a 1-1 draw by Iceland on Saturday and Spain and Portugal played to a 3-3 draw Friday.
Serbia 1, Costa Rica 0
SAMARA, Russia - Aleksandar Kolarov scored on a left-footed free kick in the 56th minute as Serbia won its Group E opener.
After Costa Rica's David Guzman was handed a yellow card, Kolarov curled the ensuing free kick over the wall, and goalkeeper Keylor Navas, who plays for Real Madrid, couldn't reach it. And now Serbia, which missed out on the 2014 tournament, has the early advantage in a tough quartet.
Costa Rica was the surprise of the last World Cup, sweeping through to the quarterfinals in Brazil before being ousted by the Netherlands on penalties to end the small Central American nation's deepest run in soccer's premier tournament. But there was some uncertainty surrounding the Ticos after a pair of friendly losses heading into this World Cup, including a 4-1 loss to Belgium a week ago.