Takanori Kamisawa, Nonuya Osodo and Kensuke Takahashi all scored twice as Japan stormed to the top of Group D with six points while Iraq are third but level on points with second-place China, leaving all to play for in the final group game between the two on Tuesday.

A frenetic start saw Kamisawa score in the second and third minute before Zaman Majid Salim reduced the deficit in the 10th minute.

Kenichiro Kogure immediately restored the lead for Japan before they ran riot in the second half with further goals from Osodo, Takahashi, Shota Hoshi, Akira Yoshida and Mitsuyoshi Matsumiya.

Japan play Turkmenistan on Tuesday while the winner of the match against China and Iraq will join them in the last eight.

Meanwhile, China scored three times in the first four minutes to post a first victory at the tournament with a 6-2 victory over winless Turkmenistan at a humid IT University Complex.

Midfielder Zhang Xi, goalkeeper Zheng Tao and striker Zhang Xiao helped China storm into an early 3-1 lead with Annaberdy Chariyev netting for Turkmenistan as the contest began at a frantic pace.

China maintained their two goal cushion at the break as midfielder Huang He added a fourth and defender Mergen Atayev kept Turkmenistan, who lost 5-3 to Iraq on Sunday, in touch.

But Liang Shuang, scorer of China's late consolation in the 5-1 defeat by Japan in Sunday's Group D opener, extended the lead five minutes after half-time before Huang's second with two minutes remaining sealed the win and ended Turkmenistan’s chances of a place in the last eight.