Tournament hosts Japan won the East Asian Championship for only the second time after a 3-0 victory over defending champions South Korea in Toyota earned the Samurai Blue their first regional title since 2013.
Second half goals from Yuki Soma, Sho Sasaki and Shuto Machino secured Hajime Moriyasu's side the win they needed to overhaul the Koreans at the top of the standings to finish with seven points from three games.
The Koreans, who had won the three previous editions of the competition, finished in second place while China sealed third spot with a 1-0 win over Hong Kong earlier in the day through Tan Long's 67th minute strike.
Japan, fielding a side made up entirely of J-League based players, dominated for long periods of the first half, with Soma coming closest to scoring in the 19th minute when his low shot beat goalkeeper Jo Hyeon-woo but came back off the post.
The Nagoya Grampus winger made no mistake four minutes into the second half, however, as he slipped in behind the Korean defence to head Joel Fujita's right-wing cross past Jo.
Soma turned provided 14 minutes later when he swung in a corner that Sasaki headed past Jo while Machino completed the win when he finished off a fine team move from close range 18 minutes from time.
Both Japan and South Korea will be among Asia's representatives at the World Cup finals in Qatar in November.
The Japanese have been drawn to face Germany, Spain and Costa Rica while the Koreans will play Uruguay, Portugal and Ghana in the group phase.