South Korea 1 Mexico 2
Mexico all-but secured safe passage to the round of 16 for a seventh straight World Cup as they eased to victory over South Korea in Rostov.
After they shocked world champions Germany in their opening Group F game, Mexico secured a 2-1 win as Carlos Vela tucked home a first-half penalty before Javier Hernandez wrapped up the points with his 50th international goal.
South Korea, who pulled a goal back in stoppage time through Son Heung-min, are all-but out after suffering a second narrow defeat but Mexico, meanwhile, are on the verge on qualification for the latter stages.
Although they are set to progress out of Group F, they will be keen to get past the round of 16 for the first time since hosting the finals in 1986.
South Korea were guilty of committing a lot of early fouls, Hernandez heading wide just after 10 minutes as Mexico looked to take advantage of one of the resulting free-kicks.
Mexico's match-winner against Germany, Hirving Lozano, bravely threw his body in front of a Hwang Hee-chan cross as Lee Yong prepared to hammer in a shot at the back-post, hurting himself in the process.
Mexico were soon ahead. Lozano initially failed to turn home a low cross and Mexico were awarded a penalty as Jang Hyun-soo was penalised for handball - referee Milorad Mazic not needing to use VAR to point to the spot.
Vela stepped up and coolly sent Cho Hyun-woo the wrong way to mark his 70th cap with the opening goal.
The lead was almost doubled shortly after but Cho was this time equal to Miguel Layun's long-range strike.
The second-half began more equally but it was Cho who was once again called into action just before the hour, tipping a deflected Andres Guardado effort behind for a corner.
Vela angled a curling strike just over the bar before Hernandez made sure of the win with a landmark goal.
Lozano burst forward as Mexico caught South Korea on the break and he teed up the West Ham striker, who cut inside before scuffing home to double the lead and bring up a half-century of goals for his country in the process.
South Korea should have got themselves back into the game as Rafael Marquez's under-hit back-pass played Son in - but he could not take advantage.
Ki Sung-yeung escaped punishment despite catching Guillermo Ochoa with a late challenge as he chased the loose ball.
With time running out, Son scored South Korea's first goal of the finals and it was one worth waiting for as he bent a 20-yard strike out of the reach of Ochoa and into the corner - but it proved too little, too late.
Juan Carlos Osorio's side now face a final group game against Sweden in Ekaterinburg on Wednesday, while South Korea take on Germany in Kazan.