Stadium: Court 1 Round: 62
| ITF Hungary F4 Qual | 2018/06/10 08:00 | Ken Onishi v Boris Butulija | 6-4,6-7,6-4 |
| ITF Czech Republic F3 | 2018/05/31 12:35 | Marek Jaloviec v Ken Onishi | 6-2,6-3 |
| ITF Hungary F3 | 2018/05/23 08:00 | Samuel Bensoussan v Ken Onishi | 6-1,6-4 |
| ITF Hungary F3 | 2018/05/22 11:20 | Ken Onishi v Matej Maruscak | 6-1,6-4 |
| ITF Bosnia and Herzegovina F1 | 2018/05/16 12:30 | Ken Onishi v Fran Zvonimir Zgombic | 6-2,3-6,4-6 |
| ITF Turkey F13 | 2018/04/01 08:30 | Ken Onishi v Gilbert S K Junior | 3-6,6-7 |
| ITF Turkey F13 | 2018/03/31 08:30 | Ken Onishi v Phongsapak Kerdlaphee | 6-4,6-2 |
| ITF Tunisia F9 | 2018/03/07 11:05 | Ken Onishi v Thomas Brechemier | 6-4,6-7,6-7 |
| ITF Hungary F4 Qual | 2018/06/10 08:00 | Filip Kucbel v Kristjan Tamm | 2-6,5-7 |
| ITF Italy F13 | 2018/06/04 07:30 | Tommaso Roggero v Kristjan Tamm | 6-2,6-3 |
| ITF Italy F13 | 2018/06/03 08:00 | Guillaume Dermiens v Kristjan Tamm | 1-6,4-6 |
| ITF Turkey F18 | 2018/05/08 07:30 | Kristjan Tamm v Alexander Weis | 5-7,0-6 |
| ITF Turkey F17 | 2018/04/29 07:30 | Kristjan Tamm v Cristian Florentin Voinea | 3-6,6-4,4-6 |
| ITF Turkey F16 | 2018/04/22 09:30 | Alexander Shevchenko v Kristjan Tamm | 6-4,6-2 |
| ITF Turkey F16 | 2018/04/21 07:30 | Ricardo David Mayagoitia v Kristjan Tamm | 6-7,2-6 |
| Cupa Davis | 2018/04/08 12:00 | Kristjan Tamm v Aziz Ouakaa | 4-6,7-5,7-10 |