ITF Thailandia F4 08/01 06:00 25 Issei Okamura v Calum Puttergill 5-7,6-0,4-6
ITF Cina F14 07/28 03:00 27 Nikola Milojevic v Issei Okamura 6-2,6-1
ITF Cina F14 07/26 02:00 26 Francis Casey Alcantara v Issei Okamura 6-4,5-7,2-6
ITF Cina F14 07/24 08:15 25 Issei Okamura v Kento Takeuchi 6-2,6-2
ITF Cina F13 07/18 07:05 25 Jui-Chen Hung v Issei Okamura 6-4,6-2
ITF Guam F1 06/21 02:30 25 Takao Suzuki v Issei Okamura 7-5,6-4
ITF Giappone F8 06/13 01:30 25 Shunrou Takeshima v Issei Okamura 6-3,7-5
ITF Giappone F7 06/07 03:35 26 Issei Okamura v Haru Inoue 6-7,2-6
ITF Giappone F7 06/06 02:40 25 Masato Shiga v Issei Okamura Retired
ITF Giappone F6 05/30 03:55 25 Kento Takeuchi v Issei Okamura 7-6,6-3
ITF Singapore F1 05/25 02:00 25 Issei Okamura v Kazuki Nishiwaki 6-7,1-6
ITF Cina F7 05/16 07:00 25 Issei Okamura v Yusuke Takahashi 7-5,2-6,4-6
ITF Cina F6 05/10 06:05 26 Dayne Kelly v Issei Okamura 6-4,6-3
ITF Cina F6 05/08 05:30 25 Ruikai Ruikai Wang v Issei Okamura 3-6,1-6
Challenger Anning - Qual. 04/22 03:35 45 Issei Okamura v Denys Molchanov 6-4,3-6,4-6
Challenger Taipei - Qual. 04/17 04:35 54 Ruan Roelofse v Issei Okamura 6-4,6-2
Challenger Taipei - Qual. 04/16 05:55 46 Shao-Fan Liu v Issei Okamura 6-7,6-4,3-6
ITF Giappone F5 04/04 00:30 25 Issei Okamura v Takao Suzuki 6-7,3-6
ITF Giappone F4 03/28 03:00 25 Kaito Uesugi v Issei Okamura 6-3,6-3
ITF Giappone F3 03/22 06:00 26 Shane Vinsant v Issei Okamura 6-2,6-3
ITF Giappone F3 03/20 02:35 25 Daisuke Sumizawa v Issei Okamura 2-6,2-6
ITF Giappone F2 03/13 04:00 25 Issei Okamura v Nam Hoang Ly 2-6,2-6
ITF Giappone F1 03/07 02:30 25 Issei Okamura v Yuki Mochizuki 2-6,4-6
ITF Cina F3 03/01 07:35 26 Issei Okamura v Marco Bortolotti 3-6,5-7
ITF Cina F3 02/28 02:00 25 Issei Okamura v Chuhan Wang Retired
ITF Cina F2 02/23 03:00 26 Issei Okamura v Jose Statham 1-6,3-6
ITF Cina F2 02/21 02:00 25 Caio Silva v Issei Okamura 1-6,0-6
ITF Maschile - Cina F1 02/15 02:00 25 Danilo Petrovic v Issei Okamura 6-3,6-2
Challenger Launceston - Qual. 02/04 01:25 46 Issei Okamura v Zach Itzstein 6-3,4-6,6-7
Challenger Burnie Qual. 01/28 04:10 46 Dane Propoggia v Issei Okamura 6-4,6-2