Phil Younghusband and Angel Guirado keyed the Azkals' victory by scoring one goal each, bringing the Philippine squad to the tournament's knockout stage.
Younghusband, who was unloading long-range shots against the Myanmar in the first half, finally found his mark from close distance in the 47th minute to push the Azkals ahead, 1-0.
Guirado, who came in for Denis Wolf, sealed the win for the Philippines with a goal in the 93rd minute.
The Philippines showed a strong defensive game early in the first half, with their backline consistently thwarting Myanmar's attempts.
Desperate for a win, the White Angels launched several attacks and found weaknesses in the Azkals' midfield midway the first half.
Gaining more confidence near halftime, Myanmar’s David Htan ran toward the Azkals goal, but his shot sailed over the cross bar.
They dominated possession but showed no goals for it because of lack of creativity in the final third.
The Azkals came roaring in the second half, with Phil controlling a long pass by Jason de Jong, before going past 3 defenders and scoring the Philippines' first goal.
Minutes later, Kaung Si Thi unleashed a dangerous attempt at the goal as he breached the penalty area.
Sacapaño cleared the attempt with a reflex save.
The Philippines nearly bagged a second goal in the 64th, but Angel Guirado's header bounced off the post.
The Azkals also suffered a scare when Phil had a collision with Myanmar’s defenders.
Fortunately, the injury was not serious and he was able to get back into the game.
In the 93rd, Guirado caught a long pass and secured the Azkals' semifinal seat by escaping Myanmar's defense to make it 2-0 for the Philippines.
It was the first time for the Philippines to beat Myanmar.
With the win, the Azkals will join host team Thailand in the knockout stage.
The Philippine will square off against the winners of Group B in the home-and-away semifinals on December 8 and 12.
The first time the Azkals reached the Suzuki Cup semis was in the 2010 edition of the tournament, when they shocked former titlist Vietnam on their way to the knockout stage.
Some of the Filipino players who were part of that 2010 squad were jubilant over the team's victory.
Fulham FC keeper Neil Etheridge was all praises for the Azkals.
"I'm so happy about the result and not even there... Feel so proud to be a part of this since 2008 what a great feeling for the players," tweeted Etheridge.
Midfielder Simon Greatwich said the win proved that the Philippine Azkals' semis finish in 2010 was no fluke.
“Great day for Philippine football. The 'whipping boys' of Asia into the semi final of the Suzuki Cup once again!" said Greatwich.