Mexico are the first team to book their place in the round of 32 at the World Cup after defeating South Korea 1-0 at Estadio Guadalajara.

Luis Romo's 50th-minute strike made all the difference for the co-hosts, following a crucial error from South Korea goalkeeper Kim Seung-gyu.

It was a quiet first half, to say the least, with the only shot on target coming in the 20th minute as Julian Quinones saw his header from the edge of the six-yard box comfortably saved.

Mexico fired an early warning shot to start the second half as Jesus Gallardo found the side-netting from a tight angle, and the opener came soon after.

After Raul Jimenez's header from Quinones' cross was blocked into the air, Kim Seung-gyu spilled his attempted catch after colliding with team-mate Lee Gi-hyuk, allowing Romo to volley into an unguarded net.

Jimenez went close to adding a second, once again being found in the box by Quinones, but the Wolves frontman saw his effort from a tight angle smothered promptly.

South Korea struggled to create many clear-cut chances after going behind, but were denied in the 87th minute by a stunning double save from Raul Rangel, who kept out Cho Gue-sung's header before reacting to stop Yang Hyun-jun's hooked shot.

Romo strikes in familiar territory

Romo made the all-important impact on his World Cup debut, scoring the goal to send Mexico back into the knockout rounds, after missing out in 2022.

Romo became the second-oldest Mexican player to score on his World Cup debut, at 31 years and 13 days. He's surpassed only by Ricardo Pelaez, who also scored against South Korea in 1998 at 35 years and 91 days.

And the midfielder scored at a venue he knows well, currently playing his club football for Guadalajara; Romo's goal was the 13th all-time goal scored by a Guadalajara player at the World Cup, and nine of those have come in the second half (69.2%).

Despite a quiet attacking display, Mexico's defence stood strong again. They have not conceded in the first half in any of their last 13 World Cup matches, since a 3-1 defeat to Argentina in 2010.

Overall, it was a lacklustre affair between the two nations, with Mexico producing 0.48 expected goals (xG) to South Korea's 0.69, most of which came from their late double-chance.

Hong Myung-Bo's side will need at least a draw against South Africa in their final Group A fixture to reach the knockout rounds, while Mexico may choose to rest players having already secured top spot.