Second-seeded Li, who dropped only one game in the tournament, overcame early stumbles to outclass the unseeded Sen 21-15, 21-12 at the Hong Kong Coliseum.
“This time my condition was not especially great, either physically or mentally, and the training was not very systematic,” Li said.
“The only way to improve faster is to join more tournaments,” he added. “It’s about using this competition to bring out my inner qualities.”
Li prevailed over Sen at the China Open in July and repeated that feat on Sunday with little pressure.
Sen’s nail-biting upset on Saturday over Chou Tien-chen from Chinese Taipei took him to his first final in two years.
In the women’s singles, top seed Wang Zhiyi took the title from defending champion and compatriot Han Yue 21-14, 24-22.
Wang told reporters the clash was “quite tough” because she was not in top form, adding that the victory over her team-mate came with a sense of “emotional release”.
China’s Liang Weikeng and Wang Chang came from behind to defeat Indian pair Satwiksairaj Rankireddy and Chirag Shetty 19-21, 21-14, 21-17 to win the men’s doubles.
Jia Yifan and Zhang Shuxian outperformed Japan’s Rin Iwanaga and Kie Nakanishi 21-17, 21-15.
The mixed doubles final was another all-China clash, with Feng Yanzhe and Huang Dongping needing just 38 minutes to beat Guo Xinwa and Chen Fanghui in two sets of 21-14. (AFP)
