Thailand's quest for the Asean Mitsubishi Electric Cup title ended in a heartbreaking 3-5 aggregate loss against arch-rivals Vietnam at the Rajamangala National Stadium on Sunday night.
Looking to overturn the 2-1 first-leg deficit, the War Elephants, who had Weerathep Pomphun sent off for his second bookable offence, suffered a 2-3 defeat in a tightly contested second-leg of the final.
Pham Tuan Hai opened the scoring after just eight minutes and Pansa Hemviboon scored an own goal late in the second half before Nguyen Hai Long sealed the 3-2 victory in the 20th minute of stoppage time for Vietnam, who claimed their third Asean title after their 2008 and 2018 victories.
Thailand scored through Benjamin Davis and Supachok Sarachat but fell just short in their attempt to win their third consecutive and eighth overall Asean championship crown.
Thailand coach Masatada Ishii congratulated Vietnam on their victory but added his players made mistakes early on which changed the outcome of the match.
"Vietnam did well so I would like to congratulate them. Our players made some errors early in the match which led to them scoring and that changed everything. We must not make those kinds of mistakes again," said the Japanese coach.
"The target before the start of the tournament was to retain the title but we also wanted to bring in some new faces into the national team. We were not able to win the title but we have new players who will go on to become great additions to the senior national team in the future.
"I would also like to thank everyone for their support throughout this month-long tournament. The fans certainly played a vital part in the team's progress to the final. I hope we continue to work together to develop the national team," he added.
Ishii made six changes to the side that lost the first leg in Phu Tho as captain Peeradol Chamrasamee, Suphanat Mueanta, Jonathan Khemdee, Thitathorn Auksornsri, Supachok and Weerathep all returned to the starting 11.
Pham Xuan Manh floated a free-kick into the box which Jonathan failed to clear while battling with Brazil-born Nguyen Xuan Son, allowing Tuan Hai to get in behind the defence and chip the ball over Thailand goalkeeper Patiwat Khammai to make it 3-1 on aggregate.
Doan Ngoc Tan gave away possession cheaply in the defensive third and Benjamin levelled the score with a stunning curling effort from 30 yards out on 28 minutes.
Vietnam suffered another blow six minutes later as Xuan Son, who scored both goals in the first leg, was stretchered off after sustaining an injury.
Supachok put Thailand 2-1 ahead to level the tie in the 64th minute with a stunning long-range strike that beat Vietnam keeper Nguyen Dinh Trieu.
Thailand were reduced to 10 men after defensive midfielder Weerathep saw his second yellow card of the night for a foul on Nguyen Quang Hai in the 74th minute and Vietnam restored their one-goal aggregate advantage eight minutes later when Thailand centre-back Pansa diverted a low cross into his own goal.
The War Elephants came agonisingly close to taking the tie to extra time when Suphanan Bureerat rattled the woodwork in the 90th minute.
However it was Vietnam who bagged the winner to put the result beyond doubt.
With Patiwat going up to attack a corner, Hai Long had an open goal to aim at on a counter-attack and he calmly rolled the ball into the goal to seal the 5-3 aggregate victory for the Vietnamese.