After returning to football in the 1990s, Vietnam did not participate in the Asian Cup for 11 consecutive editions before being selected as host in 2007 together with Thailand, Indonesia and Malaysia.
Despite these 47 years of failing to qualify, Vietnam surprised the continent in 2007 with a 2–0 victory over the UAE, a draw with Qatar and in spite of losing 1–4 to Asia's giant Japan, Vietnam qualified to the quarter-finals while three other co-hosts failed to do so, before losing to eventual champions Iraq.
However, after the dramatic run in 2007, Vietnam failed to qualify again for the 2011 and 2015 editions, before finally returning in the 2019 AFC Asian Cup.
South Vietnam would have made their second debut in the tournament, after successfully edged Singapore and Malaya in the qualification round.
Although losing the final match against Japan, Vietnam wrote history as the only host to qualify for the tournament's quarter-finals while Thailand, Indonesia and Malaysia failed to do so.
[3] Vietnam would have to wait for another twelve years to return for the AFC Asian Cup, this time to be hosted in the UAE.
By then, Vietnam was placed with strong opponents, including two former Asian champions, Iran and Iraq, with the unknown debutant Yemen.
Although Vietnam showed a great effort in the first two matches,[citation needed] the young team could not get any point.
[4] In the third Asian Cup since the country's reunification, Vietnam was grouped with Japan, Iraq and Indonesia in Group D.[5] At the dawn of the tournament, the team left with many doubts due to the absence of key players like Đặng Văn Lâm, Đoàn Văn Hậu, Quế Ngọc Hải or Nguyễn Tiến Linh due to injuries.
New hard blows were then added with the forfeit of Nguyễn Hoàng Đức, 2021 Vietnamese Golden Ball, who also failed to recover from his injury.