On July 8, Nguyễn Xuân Son played a pivotal role in Vietnam's 2-1 victory over South Korea's Yongin FC during a friendly match held in Incheon. The match showcased Vietnam's growing football prowess, especially after their impressive 6-0 win against Siheung FC, a team competing in K-League 3.

Vietnam's head coach, Kim Sang-sik, employed two different lineups for each half of the match. Notably, he separated the Brazilian naturalized players, keeping Nguyễn Xuân Son, Đỗ Hoàng Hên, and Nguyễn Tài Lộc apart in their respective formations. The first goal came early in the match, with midfielder Nguyễn Hai Long scoring in the 9th minute, marking his third goal in two matches.

Yongin FC, competing in K-League 2 and featuring quality players including Brazilian imports Gabriel Tigrao and Vitinho, managed to equalize in the 42nd minute. However, Vietnam regained the lead in the second half when Nguyễn Xuân Son scored with a powerful header in the 75th minute, securing the 2-1 win.

This victory sets the stage for Vietnam's upcoming friendly against Gangwon FC, a K-League 1 team, scheduled for July 13. Following this match, the team will return home to face Myanmar in Thái Nguyên, where they will finalize their roster for the ASEAN Cup 2026.

The ASEAN Cup will take place from July 24 to August 8, with Vietnam placed in Group A alongside Indonesia, Cambodia, Singapore, and Timor Leste. Due to the national stadium in Timor Leste not meeting hosting standards, the matches will be held at Chonburi, Thailand. Vietnam's opening match will be against Timor Leste on July 24.