China went into the Group C fixture in second place, needing only a draw to guarantee passage to the finals, but by half-time had a veritable mountain to climb.
A first-half double from Younis Mahmoud saw Iraq go into the break 2-0 up as China's chances of progression to the finals were disappearing rapidly.
Ali Adnan Kadhim made it 3-0 just before the hour-mark and although Iraq held on to a comfortable win, China's 73rd-minute consolation through Zhang Xizhe proved to be crucial as it ensured their final goal difference was minus one, securing their qualification by virtue of being the best third-placed team.
Group B's Lebanon were China’s most dangerous threat to qualifying and looked to have made themselves the best third-placed side after thrashing hosts Thailand 5-2.
Two goals from Hassan Maatouk helped Lebanon to a 5-1 lead going into the final 15 minutes and that scoreline would have been enough to guarantee progression by virtue of goals scored, but Adisak Kraisorn's 76th-minute consolation gave China the help they craved.
Malaysia ultimately came up short as well in Group D, despite a 2-1 win in Yemen to end the campaign on seven points, while it remained as you were at the top of the group after leaders Bahrain drew 0-0 at Qatar, who follow them into the finals.
Oman confirmed their place after topping Group A following a comfortable 3-1 triumph over Singapore, while Jordan defeated Syria 2-1.
Vietnam notched their first win of the qualification phase as they cruised to a 3-1 victory against Hong Kong, but it was not enough to move them off the bottom of Group E.
UAE go through to the finals after an unbeaten qualification, drawing 1-1 on Wednesday at Uzbekistan, who themselves already had second secured.
