The Strength of U23 South Korea Ahead of the Asiad 20 Quarter-Final Against U23 Vietnam: 9 European-Based Players, a 1.93m Striker and One Trap

On 25 September 2026, at 17:30 Vietnam time, Paloma Mizuho Stadium in Nagoya opens its doors for the quarter-final of the men's football tournament at the 20th Asian Games between U23 Vietnam and U23 South Korea. Over the past two weeks I have rewatched the recording of the U23 Asian Cup third-place match from January at least four times, and the moment I paused longest was not the penalty shootout. It was a second-half-of-extra-time challenge in which a Vietnamese player standing barely 1.75m rose to contest an aerial ball against a Korean centre-back almost 15cm taller, and won it. The ball went out for a throw. No goal, nobody remembers it, no news outlet wrote about it. But I remember it, because that duel told me the match in Nagoya will be decided somewhere other than where all of us are looking.

Eight months ago, against this exact opponent, U23 Vietnam drew 2-2 after 120 minutes and then won on penalties. Eight months later, the team walks into the same fixture against an almost entirely different opposing squad. The distance between those two meetings is the entire subject of this article.

Two teams arriving in Nagoya with two incomparable objectives

U23 Vietnam came to the 20th Asian Games with a young squad, largely drawn from the U21 age group, aimed at the Los Angeles 2028 Olympics. U23 Japan and U23 Uzbekistan are walking the same road. U23 South Korea are not. They brought to Nagoya a squad assembled to win gold, and that is the biggest difference between the two sides before kick-off.

The Korean side has called up nine players currently playing in Europe. Most of them play for clubs in the United Kingdom, namely England, Scotland and Wales, so pace and a strength-based approach will almost certainly be the primary plan they apply against U23 Vietnam. Based on my experience watching matches in Korean youth football for more than a decade, I have noticed a fairly stable pattern: when they manage to bring the England-based group home, their game shifts from control to physical confrontation inside the opening 20 minutes, and they are willing to trade passing volume for duels won.

Add to that three overage players: midfielder Lee Gi Hyuk, 26, currently at Gangwon FC; Yang Hyun Jun, 24, at Celtic in Scotland; and Eom Ji Sung, 24, at Swansea City in England. Those three bring more than professional experience. They bring something Vietnamese youth football does not yet have: the habit of enduring the tempo of a match in which every touch carries a price.

South Korea's consistent practice of adding overage players and Europe-based players for the Asian Games is not a coincidence. They won the last three Asian Games, in 2026, 2026 and 2026, using exactly that formula. For them, the Asian Games is a tournament that can be bought with administrative will, while the U23 Asian Cup is merely a training ground.

There is a motivation here that Vietnamese fans routinely undervalue: an Asian Games gold medal exempts male South Korean players from mandatory military service. That means the quarter-final on 25 September is not an ordinary match for them. A 26-year-old like Lee Gi Hyuk is not playing to keep his form. He is playing to trade for two years of his life. I have followed many Asian Games editions and I have never seen a Korean team enter a match with a higher level of concentration, even when they were below their technical best.

On the other side, the Korean press has been noticeably cautious. The outlet Daum wrote: "Although coach Kim Sang Sik, who knows Korean football well, is not leading U23 Vietnam, U23 South Korea cannot afford to be complacent against this opponent. In recent years, U23 Vietnam has emerged as a formidable dark horse in Asian football, relying on their characteristically solid defending and strong team spirit."

The same outlet went a step further: "This is by no means an easy opponent. In fact, the absence of coach Kim Sang Sik is acting as a catalyst that fuels the competitive spirit of the Vietnamese players. Overall, this team is still run on coach Kim Sang Sik's tactical framework. They play solidly, pragmatically, press hard and prevent opponents from building play."

The physical gap: the numbers do not lie, but they lie sideways

This is the section I want to linger on longest, because it is also the easiest to misread.

The height list for U23 South Korea at the 20th Asian Games: goalkeeper Kim Joon Hong at 1.90m; centre-back Park Seong Hoon at 1.83m; centre-back Kim Jo Soo at 1.92m; centre-back Shin Min Ha at 1.86m; central midfielder Lee Gi Hyuk at 1.84m; wide midfielder Park Seung Soo at 1.84m; forward Lee Young Jun at 1.93m; forward Kim Myung Jun at 1.82m.

On the Vietnamese side, the starting eleven so far in the tournament has usually contained only two players taller than 1.80m: goalkeeper Cao Van Binh at 1.84m and centre-back Pham Ly Duc at 1.82m. The rest are noticeably shorter, which leaves them at a clear disadvantage in aerial balls and duels.

The conventional reading of this data is that Vietnam will be killed in the air. I think that reading is correct but useless, in the literal sense of the word — it leads to no tactical decision whatsoever.

Let us do a calculation few people do. A 90-minute men's match contains roughly 55 to 65 aerial duels genuinely counted as contested headers. Most of them happen in midfield, where winning or losing the duel leads only to a throw-in or a backward pass. The headers that actually carry goal value, meaning those inside the penalty area, usually number only 8 to 12 per match, depending on the opponent's style.

In other words, height decides roughly 12 to 15 situations in a 90-minute match. The rest of the match, about 85 percent of the time the ball is in play, is decided by things entirely unrelated to height: where you stand before the ball arrives, when you begin to move, and how many bodies join the play.

That is the crux: U23 Vietnam's problem against U23 South Korea is not height, but the number of bodies inside the penalty area at the moment the ball is delivered. Height is merely the visible consequence of an invisible problem.

I once got one thing right and everything else wrong — this article is about the part I got right. In 2026, when I wrote that Germany would not survive the World Cup group stage, I relied on two numbers: an average age of 27.8 and a 12 percent drop in distance covered compared with 2026. I was right about the outcome, wrong about the player names, and mocked for it. But the lesson was not to stop predicting. The lesson was that when a number appears too clear and too easy to grasp, it is usually hiding another number.

Lee Young Jun's 1.93m is too clear a number. It hides another number.

The hidden number

The hidden number is the count of times U23 Vietnam are forced to defend in a state of lost structure.

In the 2-2 draw in January, U23 Vietnam defended well for roughly the first 70 minutes. The problem appeared in the final 20 minutes of the second half and across the two periods of extra time, when the midfield began to lose its spacing and the centre-backs had to step out of position to cover. Each time that happened, South Korea gained an extra body in the box. Each time that happened, height became a problem, because height only matters when you are free to move and meet the ball.

Put another way: South Korea's height is a dependent weapon. It only activates when U23 Vietnam lose their defensive structure. If U23 Vietnam hold their shape, Lee Young Jun's 1.93m becomes a harmless landmark in the middle of the box, waiting for a ball nobody can deliver.

This leads to a slightly counter-intuitive conclusion: U23 Vietnam's most dangerous scenario in Nagoya is not a cross from the flanks, but a counter-attack in which the ball is lost in midfield during the second half, once stamina drops and the midfielders fail to track back in time.

In modern football there is a rule I have verified across many tournaments: most goals conceded by teams physically weaker do not come from set pieces or organised crosses, but from transition moments within eight seconds of losing the ball in midfield. Height plays no part in those moments. Pace and the discipline to drop back do.

So when pundits say U23 Vietnam need to sit deep, absorb and wait for their chance, I find the proposition incomplete. Sitting deep is not a tactic. Sitting deep is a consequence of choosing where to contest the ball and where to concede it. If you concede midfield without conceding it properly, you are handing the opponent precisely the moments in which their height is unnecessary.

The contrarian angle: the trap both sides are building for themselves

This is the part where I may be wrong, and I want to state clearly that I may be wrong.

The mainstream reading before this match splits into two camps. The first says U23 South Korea will win comfortably because of height, experience and nine European-based players. The other says U23 Vietnam have a chance because eight months ago they drew 2-2 and won on penalties, because of spirit, because of character.

Both camps are looking at the past or at the record book. Neither is looking at squad structure.

South Korea's problem at the 20th Asian Games is a real and rarely discussed one: they have too many good players in the same zone. When you call home nine players from Europe, you do not get nine players evenly spread across the pitch. You get an outstanding group of midfielders and wide forwards, while the defence relies on domestic-based players shielding them. The gap between an expensive midfield and a cheap defence is where teams like U23 Vietnam can live.

I have seen this many times, and not only in Asia. National teams that assemble attacking stars tend to win through goal volume rather than control. They accept giving the opponent chances, as long as they create more. Against a pragmatic, well-drilling pressing side like U23 Vietnam, that is a door — not a large one, but a real one.

Vietnam's problem is clearer and harder to fix: they have no player capable of holding the ball for three seconds under pressure in midfield. Without a ball-holder, every counter-attack dies on the second pass. And when counter-attacks die, the team pushes up, and that is precisely when Korean height activates.

People call me controversial. I treat that as a job description.

What I will watch, and what I predict

Three things I will watch in the opening 20 minutes at Paloma Mizuho.

First, where the Vietnamese midfield stands when South Korea have the ball in their own half. If they drop level with the back line, that signals they have abandoned midfield from the start, and the match becomes an endurance test.

Second, how many times U23 Vietnam dare to keep the ball beyond two passes before hitting it long. Every extra pass is a second of rest for the defence.

Third, how South Korea build out from goalkeeper Kim Joon Hong. If they go long from the start, that signals they do not trust their ability to construct attacks against a deep block, and the match will revolve around set pieces, where height genuinely counts.

My prediction: U23 South Korea will score in the second half. Not because they are superior in height, but because U23 Vietnam will be forced to push up at some point in the second half while the score is level, and that moment is the only window in which the entire gap in physique, pace and experience opens at once.

But I also predict U23 Vietnam will score, and I think that goal will come from a situation nobody prepared for, exactly the way it arrived in the January shootout.

At 58, I have seen everything — but I have not yet seen what I am about to analyse. That is why I will still be sitting in front of the screen at 17:30 on 25 September.