Head to Head
| Japan T League | 2021/10/23 06:00 | Tomokazu Harimoto v Koki Niwa | W | 3-0 |
| World Cup | 2019/11/30 10:15 | Tomokazu Harimoto v Koki Niwa | W | 4-3 |
| T2 Diamond | 2019/11/23 12:00 | Koki Niwa v Tomokazu Harimoto | W | 2-4 |
| Qatar Open XD | 2017/06/24 07:30 | Tomokazu Harimoto v Koki Niwa | W | 4-0 |
Home History
| Japan T League | 2021/10/23 06:00 | Tomokazu Harimoto v Koki Niwa | W | 3-0 |
| Olympics 2020 - Team Men | 2021/08/06 02:30 | Woojin Jang v Tomokazu Harimoto | W | 1-3 |
| Olympics 2020 - Team Men | 2021/08/04 12:00 | Tomokazu Harimoto v Patrick Franziska | W | 3-2 |
| Olympics 2020 - Team Men | 2021/08/04 11:00 | Tomokazu Harimoto v Dimitrij Ovtcharov | W | 3-1 |
| Olympics 2020 - Team Men | 2021/08/03 02:00 | Tomokazu Harimoto v Anton Kallberg | W | 3-1 |
| Olympics 2020 - Team Men | 2021/08/02 01:30 | Tomokazu Harimoto v David Powell | W | 3-0 |
| Olympics 2020 - Men | 2021/07/27 10:30 | Darko Jorgic v Tomokazu Harimoto | L | 4-3 |
| Olympics 2020 - Men | 2021/07/26 07:30 | Tomokazu Harimoto v Siu Hang Lam | W | 4-1 |
Away History
| Japan T League | 2021/10/23 06:00 | Tomokazu Harimoto v Koki Niwa | L | 3-0 |
| Japan T League | 2021/09/22 10:00 | Koki Niwa v Mizuki Oikawa | L | 2-3 |
| Olympics 2020 - Team Men | 2021/08/06 03:00 | Youngsik Jeoung v Koki Niwa | L | 3-0 |
| Olympics 2020 - Team Men | 2021/08/04 13:30 | Koki Niwa v Dimitrij Ovtcharov | L | 0-3 |
| Olympics 2020 - Team Men | 2021/08/03 02:30 | Koki Niwa v Mattias Falck | W | 3-0 |
| Olympics 2020 - Men | 2021/07/27 12:30 | Koki Niwa v Dimitrij Ovtcharov | L | 1-4 |
| Olympics 2020 - Men | 2021/07/27 06:30 | Koki Niwa v Yang Wang | W | 4-0 |
| WTT Star Contender Doha | 2021/03/09 12:35 | Koki Niwa v Gustavo Tsuboi | L | 0-3 |