They will meet Indonesian Gwen Emily Kurniawan and Chinese Mengxi Sun, who triumphed over Kathlyn Ann Bugna and Maristella Torrecampo, 6-1, 6-4.
In other matches, Diaz and Indonesian partner Assyifa Khansa Putri Raga beat Sorvisa Kulphisanrat and Paramee Tadkaew of Thailand, 6-0, 7-6 (2), to set up a semis duel with top seeds Lee and Park, 6-2, 6-1 winners over Ai Shin Huang of Chinese Taipei and Yishan Xu of China.
In the boys division, No. 2 Jian Huang of China clobbered No. 7 Ribhav Saroha of India, 6-1, 6-1, to reach the boys’ singles final in the annual event renamed in honor of the late PHINMA Corp. chairman emeritus Oscar Hilado in recognition of his lifelong support for and contributions to Philippine tennis.
Huang will be up against No. 4 Yashwin Dahiya of India, who beat Jack Cooper of Hong Kong, 6-3, 6-4.
In the doubles, top seeds Huang and Dahiya downed Masamune Matsumoto and Luke Morgan of Japan, 6-3, 6-0, to advance to the semis against Kenzo Marcus Brodeth and Steven Cabanilla, who beat Kousuke Ko of Chinese Taipei and Saroha, 3-6, 6-4, 10-7.
The other semifinal match features second seeds Weibo Huang and Bing-Huan Tsai of Chinese Taipei against John Kendrick Bona and Stephen Yu Fuertes.
Huang and Tsai trounced Yo-Chi Chen of Chinese Taipei and Daeheon Kang of Korea, 6-1, 6-3.