Mexico became the first nation to secure a place in the knockout rounds of the 2026 World Cup, edging South Korea 1-0 in Guadalajara on a night when a single, catastrophic error decided a tense and largely featureless contest. Luis Romo tapped into an empty net five minutes after the interval, pouncing after goalkeeper Kim Seung-gyu collided with defender Lee Gi-hyuk and spilled a routine high ball. The goal, greeted by pandemonium inside Estadio Akron, proved enough to guarantee top spot in Group A with a match to spare and ensured Javier Aguirre’s side will play their last-32 fixture on home soil in Mexico City.

The decisive moment was entirely out of keeping with what had come before. A cagey first half yielded almost nothing of note: Julián Quiñones forced Kim into a comfortable save from a header, while at the other end Son Heung-min lobbed Raúl Rangel only for Edson Álvarez to clear with a bicycle kick, the effort ruled offside. The home crowd, which had booed the teams off at the break, was transformed by Romo’s intervention. South Korea, who had dictated long spells of possession without penetration, belatedly stirred. Cho Gue-sung’s close-range header in the 87th minute drew a stunning reflex stop from Rangel, who then scrambled across his line to claw away Yang Hyun-jun’s follow-up, a double intervention that Mexican commentators immediately likened to a title-winning save.

Viewed from Seoul, the defeat was a bitter pill delivered by a moment of miscommunication, yet South Korean analysts noted that the team remains firmly in contention. Hong Myung-bo’s side had opened with a 2-1 comeback win over the Czech Republic and sit second on three points, three clear of both the Czechs and South Africa, who drew 1-1 earlier in the day. A point against South Africa in Monterrey will almost certainly carry the Taegeuk Warriors into the expanded round of 32, a format introduced for the first time at this 48-team tournament. Hong, while lamenting the manner of the goal conceded, stressed that his players had executed the tactical plan and would regroup for the decisive fixture.

European observers noted the contrast in goalkeeping fortunes. Kim partially redeemed himself with a sharp save from Raúl Jiménez in the 75th minute, but the error defined the narrative. Aguirre, speaking afterwards, acknowledged the suffocating nature of the contest: “It wasn’t a great match, and the opposition didn’t allow us to do much. In the end, it felt like one mistake was always going to make the difference.” The result extends Mexico’s perfect start after a 2-0 opening win over South Africa and marks a sharp turnaround from their group-stage exit in Qatar four years ago.

Mexico will close their group campaign against the Czech Republic in Mexico City with the luxury of a dead rubber, while South Korea face South Africa simultaneously. The co-hosts already know they will meet a third-placed side from Group C, E, F, H or I on 30 June, a path that keeps them at the Azteca Stadium and, their supporters hope, deep into a tournament they have begun with unblemished defensive record and growing belief.