YEKATERINBURG, Russia — An ecstatic roar thundered across the stands in the tense closing moments of the Mexico-Sweden game here Wednesday. A joyful storm of unidentifiable liquids and debris hurtled through the air. Mexican spectators pumped their fists and hugged one another tightly.

The outburst had little to do with what was happening on the field at Central Stadium, where Mexico was disintegrating en route to a 3-0 loss to Sweden in the two countries’ vital final match of the World Cup group stage. Rather, the fans were reacting to events unfolding 600 miles away, in Kazan, where South Korea, against all odds, was beating Germany, the defending champions of the World Cup.

[Up Next: Follow our live coverage of England vs. Belgium]

The competitive permutations were complicated and plentiful as these four teams in the tournament’s Group F, singled out as the “Group of Death” for the quality of its rosters, took the field. But this development was simple enough to comprehend: Sweden was moving forward with its win and, more striking for this crowd and fans of El Tri elsewhere, Mexico was going to the round of 16, too, thanks to South Korea’s victory.