South Korea's Olympic football team returned from Japan on the afternoon of the 2nd. South Korea failed to achieve his second expected medal challenge and ended his schedule with a 3-6 crushing defeat in the quarterfinals against Mexico on July 31. Just like the 2016 Rio de Janeiro Olympics, he failed to make it to the quarterfinals. 

What the Olympic football team has lost is not only about the military service of the participating athletes. The recent achievements of the national team by age in Asia and international competitions have been a critical blow to the trend that seemed to be narrowing the gap with world football. In the match against Mexico, South Korea lost both its individual skills and team tactics, as well as its mental strength and posture. 

Romania, where all the key players who secured the Olympic finals were missing, allowed three penalty kicks and sent-off players occurred in the first half, raising concerns that the victory in the group stage against Honduras could be a trap. Most of the scores made by South Korea against Romania and Honduras came from the collapse of their opponents. No goal was scored through the process prepared through team play.

Head coach Kim Hak-beom's winning move was totally wrong against Mexico. The double full-back deployment of Kim Jin-ya and Kang Yoon-sung in preparation for the opponent's attack on the left side did not work on both sides of the offense and defense. Mexico disturbed the Korean defense organization with a play in which right-side striker Uriel Antuna came in and Luis Romo, who played in the right centre midfielder fell into the right-side.

Kang Yoon-sung struggled in a one-on-one situation, and Kim Jin-ya failed to show his firepower to control the advance of the opponent's right-back. South Korea lost a point in a side fight. In the 12th minute of the first half, Mexico's left striker Alexis Vega poked deep to the right of the door, and Romo dropped a right-footed cross pass from the right side of the door to Heather and Henry Martin finished at the door. 

Active side change easily broke down Korea's pressure defense. Basically, the pressure defense centered around the ball inevitably leaves space on the other side. Mexico's tactical preparation, which destroyed the opposite space by one-on-one response through a cross-play between a side striker and an inside midfielder, was excellent. 

After the equalizer in the 20th minute of the first half, which came from Lee Dong-kyung's personal ability, Mexico scored the second goal in the 30th minute, finishing Romo's lobbying through pass that Vega poked into the right front half-space from the left side. In this second loss, the two central midfielder combinations composed by manager Kim Hak-beom exposed their weaknesses. In fact, deploying Kim Jin-gyu, who is close to the playmaker, and Kim Dong-hyun, the central midfielder whose ball distribution is strong, did not control the penetration, breakthrough and scoring power of Mexico's second-tier strikers at all.

He believed that he could defend by pressing the team, not by individuals, but Mexico showed that organizational preparation would be in vain if he lost the world-class game one-on-one. Hwang Ui-jo, who was weak, was not an optimal striker for forward pressure. The attack pattern centered on Lee Dong-joon, the right-side striker who defeated Honduras, was controlled after a brief interaction at the beginning of the game. There was not much the striker and center-back could do in a game that was backed by both sides and the center.

Head coach Kim Hak-beom did not show steady or overwhelming performance throughout the tournament even though he won the gold medal at the 2108 Asian Games in Palembang, Jakarta. Son Heung-min lost the group stage match against Malaysia before joining the team. The contents of the round of 16 and quarterfinals against Iran and Uzbekistan were also revealed to have nothing to say. Thanks to Hwang Ui-jo's determination and Cho Hyun-woo's good defense, he reached the finals. As Son Heung-min led the defense, Hwang Ui-jo had a space.

Hwang Hee-chan and Lee Seung-woo scored goals in the final match against Japan's under-21 representative when their opponents were exhausted. He had high expectations for Hwang Ui-jo's decision at the time, but Song Bum-geun failed to show his best performance in the crisis as much as Cho Hyun-woo. While Son Heung-min was not selected, Hwang Ui-jo was often isolated from the opponent's dense defense.

Kwon Chang-hoon, who was selected as a wild card, is a good player, but he failed to show his destructive power before injury and was not used as a starting player throughout the tournament. South Korea's attack against Mexico was mainly a long ball, but the failure to select Oh Se-hoon, who was important in winning the AFC U-23 Championship, is a regret of the selection process that many point out.

Head coach Kim Hak-beom was the most likely candidate for the next national team coach if he had succeeded in the tournament. This failure will also be a big blow to Kim Hak-beom's career.

Kim Hak-beom, who had a lot of controversy from the entry selection to the composition of the selection list during the tournament, eventually failed to get enough wrong answer notes in the group stage where the pharmaceutical teams gathered, and collapsed after meeting Mexico. The process of preparing for the next international competition is a confusion that should not be repeated. The Korea Football Association should learn a lesson from this failure.