Stadium: Court C Round: 45
| Challenger Prague | 2018/07/21 14:05 | Vit Kopriva v Ljubomir Celebic | 6-1,6-4 |
| ITF Hungary F4 | 2018/06/12 08:00 | Ljubomir Celebic v Oscar Jose Gutierrez | 2-6,6-4,3-6 |
| ITF Bosnia and Herzegovina F2 | 2018/05/24 08:00 | Tom Kocevar-Desman v Ljubomir Celebic | 7-5,6-2 |
| ITF Bosnia and Herzegovina F2 | 2018/05/23 10:50 | Sebastian Prechtel v Ljubomir Celebic | 7-5,4-6,3-6 |
| ITF Bosnia and Herzegovina F1 | 2018/05/19 09:45 | Ljubomir Celebic v Nerman Fatic | 4-6,6-4,1-6 |
| ITF Bosnia and Herzegovina F1 | 2018/05/18 08:00 | Ljubomir Celebic v Tomislav Jotovski | 3-6,7-5,6-4 |
| ITF Bosnia and Herzegovina F1 | 2018/05/17 08:00 | Ljubomir Celebic v Jaimee Floyd Angele | 7-5,6-3 |
| ITF Bosnia and Herzegovina F1 | 2018/05/16 09:00 | Ljubomir Celebic v Samuel Hodor | 6-1,6-2 |
| Challenger San Benedetto Qual | 2018/07/15 08:00 | Gregoire Jacq v Nikola Cacic | 6-2,7-6 |
| Challenger San Benedetto Qual | 2018/07/14 09:15 | Nikola Cacic v Andrea Guerrieri | 6-3,6-2 |
| Challenger Perugia Qual | 2018/07/09 10:35 | Agustin Velotti v Nikola Cacic | 6-1,6-3 |
| Challenger Perugia Qual | 2018/07/08 12:10 | Nikola Cacic v Davide Natazzi | 6-3,6-3 |
| Challenger Recanati Qual | 2018/06/30 17:25 | Zhizhen Zhang v Nikola Cacic | 6-7,6-3,6-4 |
| Challenger Almaty Qual | 2018/06/09 05:35 | Nikola Cacic v Renta Tokuda | 6-7,4-6 |
| Challenger Shymkent Qual | 2018/06/04 05:00 | Jurij Rodionov v Nikola Cacic | 7-6,6-7,7-6 |
| Challenger Shymkent Qual | 2018/06/03 05:50 | Nikola Cacic v Joao Menezes | 6-4,7-6 |