| Open de Australia | 01/11 02:35 | 46 | [104] Lorenzo Sonego v Tatsuma Ito [151] | 6-7,6-0,6-7 | |
| Open de Australia | 01/10 05:25 | 45 | [246] Nicola Kuhn v Tatsuma Ito [151] | 3-6,3-6 | |
| Open de Australia | 01/08 23:00 | 44 | [151] Tatsuma Ito v Simone Bolelli [136] | 6-3,3-6,6-3 | |
| Challenger de Playford | 01/01 02:40 | 25 | [148] Tatsuma Ito v Aleksandr Nedovyesov [180] | 5-7,4-6 | |
| Challenger de Kobe | 11/18 04:30 | 29 | [236] Yosuke Watanuki v Tatsuma Ito [163] | 6-3,5-7,3-6 | |
| Challenger de Kobe | 11/17 03:00 | 28 | [213] Yasutaka Uchiyama v Tatsuma Ito [163] | 6-4,0-6,4-6 | |
| Challenger de Kobe | 11/16 04:45 | 27 | [281] Yunseong Chung v Tatsuma Ito [163] | 2-6,3-6 | |
| Challenger de Kobe | 11/14 06:25 | 26 | [362] Yuta Shimizu v Tatsuma Ito [163] | 6-7,1-6 | |
| Challenger de Kobe | 11/12 03:35 | 25 | [346] Di Wu v Tatsuma Ito [165] | 4-6,3-6 | |
| Challenger de Liuzhou | 10/24 03:00 | 26 | [346] Di Wu v Tatsuma Ito [165] | 6-3,6-4 | |
| Challenger de Liuzhou | 10/23 02:00 | 25 | [312] Sumit Nagal v Tatsuma Ito [165] | 2-6,3-6 | |
| Challenger de Ningbo | 10/19 06:40 | 27 | [173] Tatsuma Ito v Radu Albot [98] | 5-7,4-6 | |
| Challenger de Ningbo | 10/18 03:00 | 26 | [173] Tatsuma Ito v Rigele Te [413] | 6-4,6-4 | |
| Challenger de Ningbo | 10/16 10:00 | 25 | [173] Tatsuma Ito v Yusuke Takahashi [451] | 7-6,6-3 | |
| ATP Tokio | 09/30 03:50 | 164 | [184] Tatsuma Ito v Yosuke Watanuki [273] | 2-6,4-6 | |
| ATP Tokio | 09/29 04:45 | 64 | [80] Mackenzie McDonald v Tatsuma Ito [184] | 4-6,6-1,3-6 | |
| ATP Shenzhen | 09/25 12:15 | 25 | [184] Tatsuma Ito v Taro Daniel [74] | 6-2,5-7,6-7 | |
| ATP Shenzhen | 09/23 06:00 | 164 | [342] Bradley Mousley v Tatsuma Ito [173] | Retired | |
| ATP Shenzhen | 09/22 08:10 | 64 | [209] Federico Gaio v Tatsuma Ito [173] | 6-4,3-6,1-6 | |
| Challenger de Shanghái | 09/10 04:55 | 25 | [163] Tatsuma Ito v Soonwoo Kwon [272] | Retired | |
| Challenger de Zhangjiagang | 09/06 06:10 | 26 | [317] Yibing Wu v Tatsuma Ito [163] | 7-6,4-6,6-3 | |
| Challenger de Zhangjiagang | 09/04 03:45 | 25 | [336] Steven Diez v Tatsuma Ito [163] | 4-6,1-6 | |
| US Open | 08/22 19:10 | 44 | [119] Thiago Monteiro v Tatsuma Ito [165] | 7-5,6-7,6-2 | |
| Challenger de Jinan | 08/08 07:30 | 26 | [320] Roman Safiullin v Tatsuma Ito [170] | 7-6,7-5 | |
| Challenger de Jinan | 08/06 09:00 | 25 | [284] Maverick Banes v Tatsuma Ito [170] | 6-3,1-6,2-6 | |
| Challenger de Chengdu | 08/03 03:00 | 27 | [182] Tatsuma Ito v Ze Zhang [259] | Retired | |
| Challenger de Chengdu | 08/01 03:00 | 26 | Tatsuma Ito v Miliaan Niesten | 6-4,6-1 | |
| Challenger de Chengdu | 07/31 04:40 | 25 | [171] Tatsuma Ito v Danilo Petrovic [227] | 7-6,7-6 | |
| Challenger de Gatineau | 07/17 14:00 | 25 | [171] Tatsuma Ito v Maximilian Neuchrist [261] | 7-6,3-6,5-7 | |
| Challenger de Winnipeg | 07/10 16:30 | 25 | [165] Tatsuma Ito v Marc-Andrea Huesler [257] | 6-7,2-6 |