Stadium: Hard Court Central Round: 25 Ground: Hardcourt outdoor
| ITF - M15 Héraklion | 2021/05/20 06:30 | Niki, Takuto v Zhang, Ze | 5-7,3-6 |
| ITF - M15 Héraklion | 2021/05/26 10:40 | Niki, Takuto v Federico Arnaboldi | 3-6,4-6 |
| ITF - M15 Héraklion | 2021/05/20 06:30 | Niki, Takuto v Zhang, Ze | 5-7,3-6 |
| ITF - M15 Héraklion | 2021/05/19 09:45 | Niki, Takuto v Mark Whitehouse | 6-3,6-3 |
| ITF - M15 Sharm El Sheikh | 2021/04/07 12:45 | Uzhylovsky, Vladimir v Niki, Takuto | 7-6,3-6,6-4 |
| ITF - M15 Sharm El Sheikh | 2021/04/01 09:25 | Niki, Takuto v Bega, Alessandro | 3-6,3-6 |
| ITF - M15 Sharm El Sheikh | 2021/03/31 12:05 | Niki, Takuto v Fares Zakaria | 6-2,6-4 |
| ITF - M15 Sharm El Sheikh | 2021/03/25 07:30 | Niki, Takuto v Marek Gengel | 1-6,0-6 |
| ITF - M15 Sharm El Sheikh | 2021/03/24 07:30 | Toby Martin v Niki, Takuto | 2-6,2-6 |
| ITF - M15 Héraklion | 2021/05/30 06:30 | Ryan Peniston v Zhang, Ze | 6-4,6-1 |
| ITF - M15 Héraklion | 2021/05/29 06:55 | Zhang, Ze v Federico Arnaboldi | 6-2,6-1 |
| ITF - M15 Héraklion | 2021/05/28 06:30 | Zhang, Ze v Johnson, Luke | 6-1,6-1 |
| ITF - M15 Héraklion | 2021/05/27 09:25 | Zhang, Ze v Adam Jones | 6-2,6-1 |
| ITF - M15 Héraklion | 2021/05/26 13:10 | Zhang, Ze v Alexandros Skorilas | 6-2,6-1 |
| ITF - M15 Héraklion | 2021/05/21 06:30 | Yuta Shimizu v Zhang, Ze | 6-3,1-6,6-3 |
| ITF - M15 Héraklion | 2021/05/20 06:30 | Niki, Takuto v Zhang, Ze | 5-7,3-6 |
| ITF - M15 Héraklion | 2021/05/18 08:00 | Yuki Mochizuki v Zhang, Ze | 2-6,3-6 |