| Apr 24, 2026 | Nikolakis | 1–0 | Klapsakis | Round 1: Nikolakis, Konstantinos - Klapsakis, Emmanouil | Pirc Defense | |
| Apr 19, 2026 | Dionysopoulos | 1–0 | Nikolakis | Round 6: Dionysopoulos, Zacharias - Nikolakis, Konstantinos | Caro-Kann Defense: Exchange Variation | |
| Apr 19, 2026 | Synetos | 1–0 | Nikolakis | Round 5: Synetos, Dionysios - Nikolakis, Konstantinos | Caro-Kann Defense: Exchange Variation | |
| Apr 19, 2026 | Nikolakis | 0–1 | Zavrakidis | Round 4: Nikolakis, Konstantinos - Zavrakidis, Nikolaos | Rapport-Jobava System | |
| Apr 19, 2026 | Nikolakis | 1–0 | Megagiannis | Round 3: Nikolakis, Konstantinos - Megagiannis, Maximos | Rapport-Jobava System | |
| Apr 19, 2026 | Nikitakis | 1–0 | Nikolakis | Round 1: Nikitakis, Ioannis - Nikolakis, Konstantinos | Caro-Kann Defense: Tartakower Variation | |
| Apr 19, 2026 | Nikolakis | 0–1 | Georgopoulos | Round 6: Nikolakis, Konstantinos - Georgopoulos, Alexandros | Rapport-Jobava System | |
| Apr 19, 2026 | Zacharakis | * | Nikolakis | Round 5: Zacharakis, Ilias - Nikolakis, Konstantinos | ? | |
| Apr 19, 2026 | Nikolakis | 1–0 | Kosma | Round 4: Nikolakis, Konstantinos - Kosma, Erika Sevasti | Rapport-Jobava System | |
| Apr 19, 2026 | Mastichiadis | 1–0 | Nikolakis | Round 3: Mastichiadis, Dimitrios - Nikolakis, Konstantinos | Caro-Kann Defense: Exchange Variation | |
| Apr 19, 2026 | Adamopoulos | 1–0 | Nikolakis | Round 2: Adamopoulos, Vasileios - Nikolakis, Konstantinos | Indian Defense: Accelerated London System | |
| Apr 19, 2026 | Nikolakis | 0–1 | Dionysopoulos | Round 1: Nikolakis, Konstantinos - Dionysopoulos, Zacharias | Rapport-Jobava System | |
| Apr 14, 2026 | Mandridis | 1–0 | Nikolakis | Round 6: Mandridis, Pantelis - Nikolakis, Konstantinos | Queen's Pawn Game: London System | |
| Apr 14, 2026 | Nikolakis | 1–0 | Bakalakos | Round 5: Nikolakis, Konstantinos - Bakalakos, Leonidas | Queen's Pawn Game | |
| Apr 14, 2026 | Sakoutis | 0–1 | Nikolakis | Round 4: Sakoutis, Christos - Nikolakis, Konstantinos | Caro-Kann Defense: Tartakower Variation | |
| Apr 14, 2026 | Nikolakis | 1–0 | Kakos | Round 3: Nikolakis, Konstantinos - Kakos, Spyridon | Indian Defense | |
| Apr 14, 2026 | Vergopoulos | 0–1 | Nikolakis | Round 2: Vergopoulos, Panagiotis K - Nikolakis, Konstantinos | Caro-Kann Defense: Exchange Variation | |
| Apr 7, 2026 | Vompiris | ½–½ | Nikolakis | Round 6: Vompiris, Georgios - Nikolakis, Konstantinos | Caro-Kann Defense: Advance Variation, Botvinnik-Carls Defense | |
| Apr 7, 2026 | Nikolakis | 1–0 | Ainalis | Round 5: Nikolakis, Konstantinos - Ainalis, Christos Paraskevas | Rapport-Jobava System | |
| Apr 5, 2026 | Syngounis | 1–0 | Nikolakis | Round 2: Syngounis, Filippos - Nikolakis, Konstantinos | Caro-Kann Defense: Panov Attack, Modern Defense, Mieses Line | |
| Apr 5, 2026 | Nikolakis | ½–½ | Tantaroudas- Papaspyrou | Round 1: Nikolakis, Konstantinos - Tantaroudas- Papaspyrou, Harilao | Rapport-Jobava System | |
| Mar 25, 2026 | Syngounis | 0–1 | Nikolakis | Round 7: Syngounis, Filippos - Nikolakis, Konstantinos | Caro-Kann Defense: Panov Attack | |
| Mar 22, 2026 | Kosma | 1–0 | Nikolakis | Round 7: Kosma, Erika Sevasti - Nikolakis, Konstantinos | Caro-Kann Defense: Maróczy Variation | |
| Mar 22, 2026 | Nikolakis | 0–1 | Giannopoulos | Round 6: Nikolakis, Konstantinos - Giannopoulos, Stylianos | Rapport-Jobava System | |
| Mar 22, 2026 | Christodoulou | 0–1 | Nikolakis | Round 5: Christodoulou, Konstantinos Chrysovalantis - Nikolakis, Konstantinos | Benoni Defense | |
| Mar 22, 2026 | Skaperdas | 1–0 | Nikolakis | Round 4: Skaperdas, Kostantinos - Nikolakis, Konstantinos | Caro-Kann Defense: Advance Variation, Botvinnik-Carls Defense | |
| Mar 22, 2026 | Nikolakis | 1–0 | Dallas | Round 3: Nikolakis, Konstantinos - Dallas, Iasonas | Rapport-Jobava System | |
| Mar 18, 2026 | Nikolakis | 0–1 | Kalamitsis | Round 6: Nikolakis, Konstantinos - Kalamitsis, Ioannis | Queen's Pawn Game: Chigorin Variation, Alburt Defense | |
| Mar 18, 2026 | Palios | ½–½ | Nikolakis | Round 5: Palios, Panteleimon - Nikolakis, Konstantinos | Caro-Kann Defense: Main Line | |
| Mar 18, 2026 | Nikolakis | 0–1 | Matziaras | Round 4: Nikolakis, Konstantinos - Matziaras, Athanasios | Rapport-Jobava System | |
| Mar 18, 2026 | Drivas | ½–½ | Nikolakis | Round 2: Drivas, Georgios I - Nikolakis, Konstantinos | Benko Gambit Accepted: Pawn Return Variation | |
| Mar 18, 2026 | Nikolakis | 0–1 | Andreou | Round 1: Nikolakis, Konstantinos - Andreou, Antonios | Rapport-Jobava System | |
| May 3, 2025 | Nikolakis | 0–1 | Thomassin | 185th Rapid Panellinion Cafe May 2025 | Queen's Pawn Game: Modern Defense | |
| May 3, 2025 | Nikolakis | 0–1 | Fragkos | 185th Rapid Panellinion Cafe May 2025 | Indian Defense | |
| May 3, 2025 | Nikolakis | 0–1 | Alexandropoulos | 185th Rapid Panellinion Cafe May 2025 | Indian Defense | |
| May 3, 2025 | Tas | 0–1 | Nikolakis | 185th Rapid Panellinion Cafe May 2025 | Caro-Kann Defense: Two Knights Attack | |
| May 3, 2025 | Neiros | 1–0 | Nikolakis | 185th Rapid Panellinion Cafe May 2025 | Caro-Kann Defense: Tartakower Variation | |
| Apr 15, 2025 | Nikolakis | 1–0 | Paraskevas | 4th U1800 Easter Tournament, by SOXalandriou (A Group) | Queen's Pawn Game | |
| Apr 14, 2025 | Nikolakis | * | Agiakatsikas | 4th U1800 Easter Tournament, by SOXalandriou (A Group) | Rapport-Jobava System | |
| Apr 14, 2025 | Papazoglou | 0–1 | Nikolakis | 4th U1800 Easter Tournament, by SOXalandriou (A Group) | Caro-Kann Defense: Karpov Variation | |