Park Hang Seo decided to sign the contract with Vietnam national team three days earlier by changing the date from 14 October according to the previous plan to 11 October, as confirmed by Vietnam Football Federation (VFF).
The Korean will be present in Hanoi on 10 October to observe the 2019 Asian Cup qualifier between Vietnam and Cambodia.
After officially taking charge, Park will have about a month to build his team for the game against Group C leaders Afghanistan on 14 November. The Golden Stars are currently second in Group C in the third and final round of qualifying campaign.
Park has revealed his immediate attentions would be on guiding Vietnam to qualify for the final round of 2019 AFC Asian Cup.