Stadium: Hard Court 1 Round: 25 Ground: Hardcourt outdoor
| ITF Greece F7 | 2018/11/08 11:10 | Stergiou, Ioannis v Kalovelonis, Markos | 2-6,4-6 |
| ITF Greece F5 | 2018/03/28 06:00 | Kalovelonis, Markos v Stergiou, Ioannis | 3-6,2-6 |
| ITF - M15 Héraklion | 2019/05/13 09:00 | Stergiou, Ioannis v Scomparin, Pietro Romeo | 6-2,6-7,5-10 |
| ITF - M15 Héraklion | 2019/05/08 07:00 | Bothwell, Peter v Stergiou, Ioannis | 6-3,6-3 |
| ITF - M15 Antalya | 2019/04/02 07:00 | Grigoriy Lomakin v Stergiou, Ioannis | 6-4,6-4 |
| ITF - M15 Antalya | 2019/04/01 07:00 | Andrej Krajcik v Stergiou, Ioannis | 4-6,1-6 |
| ITF - M15 Antalya | 2019/03/27 07:00 | Stergiou, Ioannis v Dmitry Popko | 2-6,2-6 |
| ITF - M15 Antalya | 2019/03/26 07:00 | Tashbulatov, Dostanbek v Stergiou, Ioannis | 3-6,7-6,11-13 |
| ITF - M15 Antalya | 2019/03/25 07:00 | Sergei Pogosian v Stergiou, Ioannis | 6-7,2-6 |
| ITF - M15 Antalya | 2019/03/05 08:15 | Trinker, Bastian v Stergiou, Ioannis | 6-3,6-3 |
| ITF - M15 Tbilisi | 2019/05/03 06:00 | Kalovelonis, Markos v Mark Whitehouse | 6-3,4-6,3-6 |
| ITF - M15 Tbilisi | 2019/05/02 06:00 | Kalovelonis, Markos v Yulik, Viacheslav | 3-6,7-6,6-2 |
| ITF - M15 Tbilisi | 2019/05/01 06:00 | Kalovelonis, Markos v Ben Jones | 3-6,7-6,6-3 |
| Andijan, Singles Qualifying M-ITF-UZB-01A | 2019/04/26 07:00 | Kalovelonis, Markos v Khumoyun Sultanov | 1-6,4-6 |
| Andijan, Singles Qualifying M-ITF-UZB-01A | 2019/04/23 10:10 | Kalovelonis, Markos v Timofey Skatov | 7-6,7-5 |
| Shymkent, Singles Qualifying M-ITF-KAZ-03A | 2019/04/17 05:40 | Kalovelonis, Markos v Dubrivnyy, Artem | 1-6,4-6 |
| Shymkent, Singles Qualifying M-ITF-KAZ-03A | 2019/04/11 03:30 | Kalovelonis, Markos v Avidzba, Alen | 3-6,3-6 |
| Shymkent, Singles Qualifying M-ITF-KAZ-03A | 2019/04/10 12:05 | Kalovelonis, Markos v Korobeynikov, Grigoriy | 6-2,6-4 |