China stunned holders South Korea 3-0 at the East Asian Championship on Wednesday to give themselves an excellent chance of winning the four-team tournament.
It was China's first victory over the Koreans since they began playing full internationals in 1978.
Yu Hai headed China in front after just five minutes before Gao Lin pounced on a defensive mistake to rifle home his side's second in the 27th minute in rainy Tokyo.
Deng Zhuoxiang made it 3-0 with a clinical finish after dribbling past three defenders on the hour mark as China humbled World Cup-bound South Korea.
China have four points from two games after holding hosts Japan to a 0-0 draw at the weekend and will be favourites to beat Hong Kong in their final game.
South Korea overpowered Hong Kong 5-0 in their opening game but must now beat fierce rivals Japan on Sunday to have a chance of retaining the title.