Japan defeated hosts Malaysia 1-0 on Tuesday to secure a place at the Under-23 Asian Championship, a competition that doubles as the continent's final qualifier for next year's Rio de Janeiro Olympics.
Swiss-based striker Yuya Kubo headed in the opener shortly before halftime and that proved to be enough for Japan to finish top of first-round qualifying Group I with a maximum nine points from three games. Vietnam placed second on six points, having hammered Macau 7-0 here earlier in the day.
The 10 group winners and the five best second-placed teams join hosts Qatar at the U-23 Asian Championship in January.
"We won all three games without conceding a goal and although we only won 1-0 tonight we controlled the game without any real problems," said Japan coach Makoto Teguramori.