Top-seeded Andrey Rublev of Russia fell to unseeded Yoshihito Nishioka 6-3, 6-4, in the semifinals of the Citi Open in Washington, D.C. on Saturday night.
Nishioka, of Japan, will play Australia's Nick Kyrgios in Sunday's finals. Kyrgios defeated Mikael Ymer of Sweden 7-6 (4), 6-3 in the other semi.
Rublev recorded five aces but suffered four double faults. He won just 31 percent of his second serves.
Kyrgios needed one hour and 34 minutes to oust Ymer. Kyrgios blasted 10 aces without a double fault.
Abierto de Tenis Mifel
Russian Daniil Medvedev defeated Cameron Norrie of Great Britain 7-5, 6-0 to claim the championship at Los Cabos, Mexico.
The top seed and World No. 1 defeated Norrie in one hour, 21 minutes. Medvedev finished with five aces against just one double fault. Norrie recorded three double faults and won just 42 percent of his first serves.
Medvedev had lost his past five championship matches, including last year's ATP Finals and the Australian Open in January.
--Field Level Media