The first round of the men's golf domestic tour tournament was held in Hokkaido, and South Africa's Jave Kluger took the lead alone with a 7-under.
Kluger took the lead by marking a 7-under with one eagle and five birdies.
Ryuko Tokimatsu and Hiroyo Ikemura were in second place with a one-stroke difference, and Hiroshi Iwata and nine others were in fourth place with a one-stroke difference.
Rikuya Hoshino and Ryo Ishikawa, who are the top prize money players in the Tokyo Olympics, were 13th with 4 unders, 3 strokes behind the lead.
Shugo Imahira, who won the championship last week, was 22nd with 3 unders.