Co-hosts Mexico became the first team to reach the knockout rounds of the World Cup with a 1-0 win over South Korea at a delirious Guadalajara Stadium on Thursday.
Luis Romo’s goal just after half-time put Mexico through as Group A winners with a match to go following a goalkeeping clanger.
In contrast, Mexico stopper Raul Rangel made a superb double save in the dying minutes to preserve their lead.
Finishing top keeps Mexico at home in the last 32 with a game against a third-placed team in Mexico City.
South Korea are second on three points, with the Czech Republic and South Africa also still alive on one.
Both teams went into the clash in front of a passionate home crowd knowing that victory would guarantee progress in double-quick time.
Mexico coach Javier Aguirre made three changes from the side that beat South Africa 2-0 a week ago to open the tournament.
His counterpart Hong Myung-bo made just one alteration, largely keeping faith with the team that fought back to defeat the Czech Republic 2-1.
South Korea skipper Son Heung-min had the first sniff at goal after 15 minutes, looping the ball over Rangel only for Edson Alvarez to prevent it going in with a bicycle kick on the line.
Los Angeles FC attacker Son was belatedly flagged for offside although replays suggested it was a close call.
Julian Quinones, who scored the opening goal of the tournament, then forced South Korea goalkeeper Kim Seung-gyu into a good save from a header, raising the decibels.
The rest of an uneventful half belonged to South Korea as they stroked the ball around at will, without ever creating a clear chance, but they did succeed in silencing the home support.
Jeers rang out at half-time from the Mexico fans.
The hosts started the second period with far more intent, and five minutes in they went ahead when the goalkeeper Kim came for a high ball and clattered into his own player, spilling it straight to Romo.
He just needed to poke the ball first time into an unguarded net, triggering pandemonium.
Hong surprisingly hauled off the veteran talisman Son before the hour and threw on Hwang Hee-chan of Wolverhampton Wanderers.
But the Koreans were mostly toothless going forward until the final few minutes, when Guadalajara native Rangel came to Mexico’s rescue.
They will face the Czech Republic in their dead-rubber final group game while South Korea play South Africa.
South Africa and the Czechs drew 1-1 earlier in the day.
