The national Under-18 football team fell to a 5-0 defeat to South Korea in their third Group B game of the 41st Asian Schools Football Championships yesterday.
It was only a day after the team enjoyed their first victory in the tournament defeating Macau 2-1, but they were quickly brought crashing back to earth by last year's semi-finalists at the Mae Fah Luang University in Thailand.
In an interview with The Brunei Times, national coach Tajul Ariffin Sumpong said that South Koreans were at another level.
"They were just too strong and fast," said Tajul in a telephone interview.
"Physically they are taller and bigger than our players too.
"Our players gave their all in the game but it was just too difficult.
"We played with five defenders at the back in the first-half and we conceded three goals, so in the second-half we decided to put six at the back to defend - but we still let in two goals.
"The South Koreans were playing long balls for most part of the game.
"Most of their goals came from set-pieces and our defenders were having a hard time defending.
"We were also without three of our first eleven in the game, so it was a bit difficult," he added.
Ak Yura Indera Putera Pg Yunos was unavailable after collecting yellow cards in the previous games while Muhd Nadzri Hj Erwan and Ak Md Azreen Eskandar Pg Hj Saoda were also out because of injuries.
Brunei started out their campaign with a 2-0 loss to China on Friday before notching their first win against Macau on Saturday.
The Sultanate will play their last game against Vietnam today and Tajul knows that anything less than three points would bury any hopes of finishing in the top two spots in the group - and gain entry to the semi-finals.
"We must win tomorrow (today)," insisted Tajul.
"If we lose we won't have any chance at qualifying.
"South Korea and Vietnam are tied with us with three points, and they haven't met China yet, so we must get the three points tomorrow.
"We will welcome Ak Yura Indera Putera back in the team after suspension but Muhd Nadzri and Ak Md Azreen Eskandar are still out with injuries," he added.
But no matter if they win or lose, their outing in Thailand is already a marked improvement from last year's trip to Iran where they lost all four games and failed to find the net even once.
Brunei lost 4-0 to Malaysia during their first match and fell to Thailand by the same scoreline the next day.
Hong Kong beat them 2-0 and China went past them 4-0.
This year's team included two players who participated in Tehran, where the altitude - Shahid Bahoner Camp is almost 3000m above sea level - played a huge part in the losses.
Iran, who scored 53 goals and didn't let in a single one, were crowned champions after a 2-0 triumph over Thailand.
However, they did not join this year's event.
The other pool has Hong Kong, Indonesia, Malaysia, Sri Lanka and Thailand grouped together in Group A.