Dinh Bac quietly walked past coach Kim, heading straight into the dressing room as the first half ended.

The 0-0 draw between Vietnam and Singapore in the third match of Group A of the ASEAN Cup 2026 not only left regrets over missed opportunities but also drew attention due to striker Nguyen Dinh Bac's reaction after being substituted off in the first half.

In the 41st minute, coach Kim Sang-sik made a surprising decision by pulling Dinh Bac off the field and sending Nguyen Tai Loc on as a replacement. This was a rare adjustment, as the match had not yet reached halftime and the player was not injured. The move showed that the South Korean coach wanted to immediately change the attacking approach, given that Vietnam was struggling against Singapore's packed defense.

According to footage captured by television, Dinh Bac showed dissatisfaction with the coaching staff's decision. Before leaving the pitch, the 2004-born striker signaled to be allowed to continue playing, but coach Kim Sang-sik maintained his decision.

As he approached the technical area, Dinh Bac displayed gestures of disappointment. He spread his arms while listening to the head coach's comments, before shaking hands with the coaching staff. However, the most notable moment came after the first-half whistle. Instead of staying to exchange further words, the Vietnam striker quietly walked past coach Kim Sang-sik and headed straight into the tunnel to return to the dressing room.

Dinh Bac's actions quickly became a topic of discussion on social media. Although no verbal exchange was recorded, the 22-year-old striker's pensive expression and manner of leaving the pitch showed that he could hardly hide his disappointment at being substituted too early.

Against Singapore, Dinh Bac had an underwhelming game compared to his explosive performance in the 7-0 victory over Timor Leste, where he scored a hat-trick. Despite being given a starting spot by coach Kim Sang-sik, the striker missed three clear chances in the first half. The most unfortunate were two situations where the goal was almost open, but his finishes lacked accuracy.

Coach Kim Sang-sik's substitution decision was seen as a clear message about competition within the team. The South Korean coach is willing to give opportunities to any player in good form, but also does not hesitate to make tough adjustments if performances do not meet tactical requirements. For Dinh Bac, the forgettable 41 minutes against Singapore could be a valuable lesson for the young striker to quickly regain confidence ahead of the crucial match against Indonesia in the next round.