Second-half goals from Thanabalan Nadarajah and Muhammad Syazwan gave Malaysia a 2-0 victory over 10-man Mongolia in Bangkok on Sunday to secure qualification for January's 2018 AFC U23 Championship in China.
Their passage was confirmed when host nation Thailand were held to a 0-0 draw by Indonesia in a later match on Sunday night, allowing Datuk Ong Kim Swee's team to finish top of Group H.
It was also a huge boost for the Malaysians ahead of the men's football tournament at next month's Southeast Asian (SEA) Games in Kuala Lumpur.
Even so, it was an unimpressive performance from the Malaysians, with Mongolia the better side before being reduced to 10 men. But Harimau Malaya deserve credit for sticking to their guns to secure a second victory in three matches in Thailand.
But the Mongolians almost stunned Malaysia in the fourth minute. They sliced through the Malaysian backline, and Gal-Erdene Soyol-Erdene was muscled off the ball just in time as he looked set to tap in Enkhbileg Purevdorj's cut-back to the far post.
The minnows threatened again in the 17th minute as Tuguldur Munkh-Erdene broke down the left and found Tserenbayar Boldbaatar in space in the Malaysian box. The midfielder's control let him down, however, and he scuffed his shot wide.
Malaysia came close in the 22nd minute when a low ball across goal reached Akhyar Rashid, but the playmaker completely missed his kick. Shamie Iszuan gathered the ball and fed it back to Thanabalan near the edge of the box, but the Felcra striker blazed it high over.
However, Mongolia continued to look the more threatening. First, a low cross from Enkhbileg just evaded Altansakuh Temuujin at the back post before a surging run from Narmandakah Artag was ended by a crude foul 30 yards from goal.
With his side being outplayed by the group underdogs, Ong had seen enough, and made a double substitution with just 37 minutes gone.
Shamie was replaced by Syahmi Safari and Mohd Fauzan came off for Syafiq Ahmad.
The Malaysians worked their way back into the game towards the end of the half. But Mongolia head coach Michael Weiss will have been much happier than his counterpart with the first 45 minutes.
But Malaysia breathed a huge sigh of relief when they took the lead against the run of play in the 51st minute. Ashraf cut the ball across the face of goal and Thanabalan bundled the ball home from inside the six-yard box.
Six minutes later, Akhyar's darting run down the left was ended by a lunge from Uuganbat Bat-Erdene and the Mongolian defender was given his second yellow card.
The tiring Mongolians continued to battle gamely and when Ganyabar Ganbold flashed two shots wide with just over 10 minutes remaining, it reminded Malaysia that there was still work to do.
But Syazwan finally killed off the Mongolians with an excellent strike in the 86th minute. He cut inside from the left and arrowed an unstoppable shot into the top corner from just inside the penalty area.