Monday night's one-goal loss to Indonesia at the games — an event seen as a "coming out" party for Myanmar after major reforms — devastated local fans who have filled the 50,000 Yangon stadium to capacity during the group stage.
Trouble flared inside the Yangon stadium before full-time and then carried on after the game with furious fans setting alight police posts and billboards, police told AFP Tuesday.
"We detained eight football fans last night, including two who invaded the pitch in second-half," according to deputy police colonel Min Aung from national police headquarters.
Hooliganism at Myanmar's football matches is common. In August fans destroyed the pitch at a new stadium in the capital Naypyidaw, where Indonesia will now travel to contest the semifinals.
In 2011 Myanmar were banned from World Cup qualifiers by the sport's organizing body after a home tie against Oman had to be stopped when the crowd pelted the opposition with bottles and rocks.
The ban was lifted on appeal.
Television images on Monday showed distraught fans being consoled by Zaw Zaw, a tycoon and chairman of the Myanmar Football Federation.
"We had high hopes for the Myanmar team. We even planned to go to Naypyidaw today to watch the semi--final," fan Phone Myint Khaing told AFP. "I'm lost for words to describe how sad we are. It's heartbreaking."
Blame swiftly fell on Myanmar's Korean coach as the home side failed to progress despite sharing points with Indonesia and having a better goal difference.
Park Seong-Hwa was dismissed after the match, with local reports saying he admitted he was unaware of competition rules stating that the head-to-head result — and not goal difference — would determine who progresses if teams were tied on points.
"I knew only after the match as Myanmar finished the group level. I would like to apologize to Myanmar," he said, according to Eleven, a daily newspaper.
He had previously talked up Myanmar's chances of claiming gold in the games, which are being held in the country for the first time in 44 years.