Vietnamese Football After AFF Cup 2026: From the Throne to the Tactical Puzzle of the Post-Kim Sang-sik Era

When the final whistle echoed through Rajamangala Stadium on the evening of January 5, 2026, millions of Vietnamese hearts burst with joy. The third Southeast Asian championship trophy had returned to the national team, a historic achievement built on a foundation of patience, tactical discipline, and collective spirit. However, as the spotlight faded and emotions settled, I realized that this victory was not an ending, but the beginning of a deeper tactical dialogue about the future of Vietnamese football. Having followed and analyzed Asian football for 28 years, I have never witnessed a moment so proud yet so full of tactical questions. The journey to the Southeast Asian throne was not just a story of goals or miraculous saves. It was a story of a meticulously organized defensive-counterattacking system, a geometric pressing block operating like a precise machine, and a coaching staff that understood their own limitations. I watched every match of the national team in this tournament, and what impressed me most was not the victory over Thailand in the final, but how the team handled transition situations – from defense to attack – with extreme rationality and minimal risk. However, the biggest question I ask after this victory is: is the success at AFF Cup 2026 a sustainable foundation for long-term development, or just a temporary peak created by luck and fighting spirit? To answer this question, we need to look deeper into the tactical structure, player quality, and more importantly, the youth development system operating behind the national team. When analyzing the tactics of the Vietnamese national team under coach Kim Sang-sik, I noticed a clear shift compared to the ball-possession philosophy of his predecessor Park Hang-seo. If Park Hang-seo built a playing style based on defensive solidity and discipline, Kim Sang-sik refined this system to be more flexible and varied in counter-attacks. Data from AFF Cup 2026 matches shows that Vietnam only averaged 43% ball possession in knockout matches, but scoring efficiency was superior with a 22% chance conversion rate. This is a notable figure, showing the difference between controlling the ball and controlling the match. What interests me most is how Kim Sang-sik arranged the pressing block. Unlike the high pressing that many Asian teams are applying, Vietnam chose a mid-block pressing strategy, aiming not to win the ball immediately but to force opponents to pass into less dangerous areas. This approach was particularly effective against Thailand's technical style, preventing them from smoothly building up play from the back. I analyzed Vietnam's PPDA (Passes Per Defensive Action) index in this tournament, and the average of 11.4 shows they did not actively rush into ball challenges but waited for opportunities to strangle opponents at key moments. However, no tactical system is perfect, and I always look for blind spots in teams' play. Vietnam's biggest weakness in this tournament lay in defending aerial duels and high-speed wing attacks. In the semi-final against Singapore, the team faced great difficulties against crosses from the flanks, and only the excellence of goalkeeper Dang Van Lam kept Vietnam's clean sheet. This is a warning sign that the defense still has gaps in handling aerial situations, a problem that West Asian or East Asian teams could exploit thoroughly if Vietnam advances further in continental competitions. Another aspect I want to mention is the team's dependence on some key players. Nguyen Hoang Duc, with his ability to regulate match tempo and precise long-range passes, has become the soul of the team's play. Similarly, Nguyen Tien Linh, with his intelligent positioning and diverse finishing, is the most important spearhead in attack. However, this dependence is also a potential risk. If one of these players gets injured or loses form, does the team have enough squad depth to replace them? Based on what I observed from recent friendly matches, the answer is still a big question mark. Speaking of squad depth, I want to emphasize that Vietnamese football's success lies not only in the national team but also in the youth development system. In recent years, Vietnam's U23 and U19 generations have achieved certain successes at the regional level, but the quality gap between age groups remains quite large. I have witnessed many other Asian countries, like Japan or South Korea, building systematic and synchronized youth development systems, from selection to professional training processes. Vietnam needs to learn from these models to create a stable supply of quality players for the national team in the future. The youth training issue in Vietnam also raises a big question about training philosophy. Should we prioritize developing individual technique or building collective tactical thinking? From a sports science researcher's perspective, I believe there needs to be a balance between these two factors. Good individual technique helps players be more confident in one-on-one situations, while good tactical thinking helps them make the right decisions in complex situations. Youth academies in Vietnam need to build a comprehensive training program, combining both factors harmoniously, instead of focusing only on one single aspect. Another issue I want to address is the development of domestic leagues. V.League 1, the highest division of Vietnamese football, has made significant progress in recent years, with strong investment from clubs and growing interest from fans. However, the professional quality of the league still has many limitations, especially in tactical organization and players' physical condition. I notice that many clubs in V.League 1 still rely too heavily on foreign players of uneven quality, leading to imbalance in play and failing to create a healthy competitive environment for young domestic players to develop. The Vietnam Football Federation (VFF) needs to implement stronger policies to improve V.League 1 quality, such as tightening regulations on the number and quality of foreign players, while creating conditions for young players to play more regularly. Limiting the number of foreign players on the field at a reasonable level will create more opportunities for domestic players, thereby improving the quality of the national team squad. This is not an easy puzzle to solve, but if done, Vietnamese football will have a much more solid foundation for development. Returning to the national team, I want to analyze deeper the role of coach Kim Sang-sik in the recent success. Kim Sang-sik, a former center-back with a long career in K League 1 and an assistant to coach Park Hang-seo for the Korean national team, has brought a fresh breeze to Vietnamese football. He not only inherited the values that Park Hang-seo built but also made subtle adjustments to fit the current context. The most important adjustment I noticed is the flexible use of tactical formations, from 3-4-3 in matches against stronger opponents to 4-2-3-1 when needing to control the game. However, I also noticed some limitations in Kim Sang-sik's tactical execution. At certain moments of the match, Vietnam tended to drop too deep into their own half when pressured by opponents, creating large gaps between lines. This not only made it difficult for the team to build up play but also allowed opponents to take dangerous long-range shots. I counted that in the first leg of the final against Thailand, Vietnam conceded up to 7 shots from outside the penalty area, a relatively high number, showing that the midfield line did not do well in controlling the space in front of the defense. Another notable point is the difference in match approach between the two final legs. In the first leg at Viet Tri Stadium, the team played more proactively with high pressing intentions and more ball possession. However, the result was only a 1-1 draw. In the second leg at Rajamangala, Kim Sang-sik made bold adjustments by proactively ceding the game to Thailand and playing defensive counter-attacks. This change shows the flexibility in the Korean coach's tactical thinking, but also raises the question of whether the team should be more proactive in important matches. I believe there is no single winning formula in football, and the choice of playing style depends greatly on the opponent and specific context. However, to advance further in major arenas like the Asian Cup or World Cup qualifiers, the Vietnamese team needs to be even more flexible in their play, able to proactively control possession when needed but also ready to switch to defensive counter-attacks when facing stronger opponents. This flexibility requires players to have good technical and physical foundations, along with sharp tactical thinking. Looking to the future, I believe Vietnamese football is at an important crossroads. The success at AFF Cup 2026 is a clear demonstration of the potential for development of Vietnamese football, but it is also a reminder that we cannot rest on our laurels. To maintain and develop this success, Vietnamese football needs a long-term, systematic, and synchronized development strategy, from the youth training system to the quality of domestic leagues, from coach selection work to building a professional and sustainable football environment. One of the issues that concerns me most is the gap in level between Vietnamese football and Asia's leading football nations like Japan, South Korea, or Iran. This gap lies not only in the technical and tactical level of players but also in infrastructure, training work, and even football culture. To narrow this gap, Vietnam needs to take bolder and more decisive steps, not only at the national team level but across the entire domestic football system. I also want to emphasize that football is not just a sport but also an entertainment industry with great influence on society. The development of Vietnamese football not only brings pride to fans but also creates significant economic opportunities, from attracting investment into clubs to developing related media and entertainment products. However, this development needs to be managed sustainably and responsibly, avoiding investment bubbles or negative consequences for society. In that context, the role of media is also very important. I notice that Vietnamese media has made significant progress in covering football, with many in-depth analysis programs and quality articles. However, there is still a lot of unverified information, sensational or unobjective articles. As a journalist with nearly three decades in the profession, I believe media needs to be more responsible in providing accurate and objective information, contributing to building a healthy and positive football culture. Returning to the question I posed at the beginning of this article: is the success at AFF Cup 2026 a sustainable foundation for the long-term development of Vietnamese football? My answer is: possibly, but only if we correctly understand what has been achieved and what needs to be done next. This victory is an important milestone, but it is not the final destination. Vietnamese football needs to continue developing systematically and sustainably, with the joint efforts of all stakeholders, from the Federation, clubs, to fans and media. I want to end this article with a strategic assessment: Vietnamese football has proven that it can compete and win at the regional level, but to reach continental heights, there needs to be a revolution in thinking and methodology. We cannot forever rely on fighting spirit and luck; we need to build a modern, scientific, and professional football system. This is a long and challenging journey, but I believe that with what has been shown, Vietnamese football can go even further in the future.