MOSCOW - Less than 60 seconds after a chorus of "Oles" broke out among the Mexican fans in the 34th minute, cheering on every pass their team made, the underdogs went ahead.
El Tricolor went on another thrilling fast break and pandemonium broke out when crowd favourite Hirving Lozano received Javier Hernandez's pass, skipped past Mesut Ozil, and blasted into Manuel Neuer's net.
"Es Chucky Lozano! (It's Chucky Lozano)," sang the Mexican faithful, in tribute to the 22-year-old PSV Eindhoven winger who bears a striking resemblance to the scary doll from the Child's Play horror movies when he grins.
With his electrifying pace and direct runs, Lozano proved a nightmare for the German defence, who were unusually panicky against the Mexicans' high-pressing game.
A day after Iceland held Argentina 1-1, the World Cup produced another major shock on Sunday (June 17) when world champions Germany suffered the same fate as 2010 champions Spain, who were thrashed 5-1 by the Netherlands in their opening match in Brazil four years ago.
Joachim Low's men looked mediocre in front of 78,011 spectators in the 1-0 defeat, as they appeared bereft of pace and ideas in the Group F opener.
Outside the Luzhniki Stadium, the Mexicans had already comfortably won the fancy dress contest with their sombreros, huipil, Aztec warrior costumes and lucha libre masks.
The infectious exuberance carried on to the pitch after the first whistle as the central Americans took the game to Germany, whose central defender Jerome Boateng was so confused on one occasion that he spun one round before he regained his bearings.
After exploiting huge swathes of space between the halfway line and the German penalty area on numerous occasions before finding a breakthrough, Mexico showed they could also defend their lead.
While they invited Germany to attack so they could hit on the counter, centre-backs Hector Moreno and Hugo Ayala held firm.
On the rare occasion Guillermo Ochoa was called into action, the goalkeeper flew across goal to tip Toni Kroos' free kick onto the bar.
Inspiration was nowhere to be found from Germany's starting XI nor their bench.
Timo Werner demonstrated pace but not much else, raumdeuter Thomas Muller could not find space to add to his 10 World Cup goals, and Ozil was closer to his clueless worst in an Arsenal shirt.
Low also looked silly for leaving out Manchester City's Leroy Sane as no other German could top his 14 goals and 17 assists last season, and substitute Mario Gomez failed to make any late impact.
Goalkeeper Neuer's late foray for a corner proved futile as the Mexican fans celebrated as if they had won the tournament.
For now, it seems as if Germany are in danger of being struck by the curse that has befallen recent winners - France (1998), Italy (2006), and Spain (2010) all crashed out in the group stage at the next World Cup. There have also been just two back-to-back winners - Italy (1934 and 1938) and Brazil (1958 and 1962) - while no world champions have emerged from Group F.
Even if Low and his team are not superstitious, and still fancy themselves to beat Sweden on Saturday and South Korea (June 27), they have to improve in all departments to wake up from this bad dream, and fast.