Thehost team defeated Thailand 2-1 in the third-round match on Tuan ChauIsland.
Thefirst half saw Vietnam attack rapidly and they quickly went ahead.
LaVan Lon, Le Van Binh and Nguyen Chi Tam took the responsibility of scoringfor the hosts, who received strong support from residents and tourists.
Theyended the first set at 21-12.
The15-minute interval was worth it for the Thais who came back stronglywith more threatening attacks that put them ahead in the set.
CoachTrinh Huy Cuong urged his players to strengthen their defence and fight backbut his players could not narrow the gap. The second set ended at20-16 for the visitors, leading to a shoot-out.
Itwas the first set lost by Vietnam, the defending champions.
Theshoot-out was neck-on-neck, reaching 10 apiece. Goalkeeper Vo Vuong Trongended up the hero of the Vietnamese side, denying many powerfulfinishes as Vietnam eventually ran out 18-16 winners.
Earlier,Vietnam had beaten Singapore and the Philippines, both 2-0.
Withthree wins, Vietnam are top of the ranking table and have one hand on thechampionship trophy, although there are three more matches to go.
Inthe earlier game on May 8, the Philippines beat Singapore 2-0.
Thereare four teams taking part in this event, competing in a two-leg round-robinformat. The team with the best points will take gold on May 11, one day beforethe opening ceremony.
Initially,five teams registered to take part in the men's beach handball, beforeIndonesia dropped out.
Theyalso pulled out of the women's category, leading to the cancellation of thisevent. Their decision left only two teams, Vietnam and Thailand, andregulations rules a tournament can only take place with at least threeteams.
TheVietnamese women could not compete at the SEA Games 31 but they recently wonthe Asian championship. They will be continental representatives at the worldchampionship in Greece in June and the World Games in the US inJuly./.