Japan promptly displayed their strength as reigning runners-up by winning the first set 25-16 before claiming the second with a score of 25-22.
Seeming to be a disappointing day for Vietnam, the team made an incredible resurgence with their decisively competitive spirit.
Vietnam drew back two games both with a score of 25-22, forcing the match to be decided in the fifth set, where Vietnam led 7-5, 11-8 and 13-9 before finishing off the Japanese opponents 18-16.
It was the second time Vietnam overcame Japan at the national level. Vietnam once conquered Japan 3-2 at the 2012 AVC Asia Women's Cup in Almaty, Kazakhstan.
Vietnam will take on Mongolia on May 21 before facing Turkmenistan in the last group game the following day.
The biennial event is taking place in Tianjin, China from May 20 to 28, gathering 16 teams competing in a round robin format in four groups, with the top two teams from each group qualifying for the quarterfinals.
At the previous competition in Thailand two years ago, Vietnam ended up in sixth place overall after losing 2-3 to Kazakhstan, while Thailand crushed Japan 3-0 to claim their second championship, following the first in 2009.
(Source: Nhandan Online)