Portugal’s Marcos Freitas caused an early upset in the men's singles event at the International Table Tennis Federation (ITTF) Korea Open by defeating seventh seed Lee Sang-su in Busan.
Freitas held his nerve to close out a thrilling 8-11, 11-8, 6-11, 11-7, 7-11, 11-8, 11-7 victory in seven games at the ITTF World Tour Platinum event at Sajik Arena.
The Portuguese player's reward is a meeting with China's Wang Chuqin, who beat Lin Yun-Ju of Chinese Taipei 11-6, 11-8, 11-9, 11-9.
Newly-crowned world number one Xu Xin of China swept aside Japan’s Yuki Hirano 11-6, 11-1, 11-2, 11-4 to join Freitas in round two.
Xu's opponent is set to be Nigerian veteran Quadri Aruna, a 2-11, 11-8, 13-11, 11-9, 11-3 winner in his clash with Germany's Benedikt Duda.
Top seed Fan Zhendong survived a scare against compatriot and qualifier Xu Chenhao as he lost the opening two games before recovering to claim a 5-11, 8-11, 11-9, 11-9, 10-12, 11-9, 11-4 victory.
In the women's singles event, top seed Ding Ning of China was also forced to come from behind as she dropped the opener in her match with team-mate He Zhuojia.
Reigning Olympic champion Ding eventually showed her class as she fought back to win 9-11, 11-7, 11-7, 11-7, 11-8.
China’s Chen Meng and Wang Manyu, both considered challengers for the Korea Open title, were among the other winners.
World number one Chen defeated Japan's Honami Nakamori 11-5, 11-3, 11-5, 11-8, while Wang beat India's Commonwealth Games champion Manika Batra 11-8, 11-4, 11-7, 13-11.