The Japanese clogged up the leaderboard as Shiho Kuwaki and Nasa Hataoke signed on similar 66s on Saturday to share the lead with one round to go in the LPGA Japan Classic in Omitama, Ibaraki, Japan.
Kuwaki and Hataoke hold a one-shot advantage with a 20-under total of 196.
Compatriot Mone Inami is at solo third place after a 65 to go one shot behind, while Sara Kamiya is at solo fourth following a similar 65, two shots away from the co-leaders.
Yuri Ishida led the bottleneck for fifth place after carding a 65 and going two shots further behind.
Japanese-Filipina Yuka Saso is at shared 24th eight strokes off the leaders despite a 67 on Saturday.