| Jun 1, 2026 | O`cuilleanain | 1–0 | Nichenametla V | Round 6: O`cuilleanain, Oisin - Nichenametla V, Advaith | Catalan Opening: Closed | |
| Jun 1, 2026 | Melaugh | 0–1 | O`cuilleanain | Round 5: Melaugh, Shane - O`cuilleanain, Oisin | English Opening: Agincourt Defense | |
| May 31, 2026 | O`cuilleanain | 0–1 | Fil | Round 4: O`cuilleanain, Oisin - Fil, Alkim Alper | Sicilian Defense: O'Kelly Variation, Réti System | |
| May 31, 2026 | Andhurthi | 0–1 | O`cuilleanain | Round 3: Andhurthi, Sreeyan - O`cuilleanain, Oisin | Sicilian Defense: Najdorf Variation, English Attack | |
| May 30, 2026 | O`cuilleanain | 0–1 | Barnes | Round 2: O`cuilleanain, Oisin - Barnes, Oliver | English Opening: Agincourt Defense, Neo-Catalan Declined | |
| May 30, 2026 | Hughes | 1–0 | O`cuilleanain | Round 1: Hughes, Padraig - O`cuilleanain, Oisin | Sicilian Defense: Najdorf Variation, English Attack | |
| Apr 26, 2026 | O`cuilleanain | 1–0 | Arun | Round 5: O`cuilleanain, Oisin - Arun, Nitish | Queen's Indian Defense: Fianchetto Variation, Nimzowitsch Variation | |
| Apr 26, 2026 | Sean J. Murphy | 0–1 | O`cuilleanain | Round 4: Sean J. Murphy - O`cuilleanain, Oisin | Queen's Gambit Declined: Queen's Knight Variation | |
| Apr 25, 2026 | Delaney | ½–½ | O`cuilleanain | Round 3: Delaney, Killian - O`cuilleanain, Oisin | Sicilian Defense: Alapin Variation | |
| Apr 25, 2026 | O`cuilleanain | 1–0 | Nordgreen | Round 2: O`cuilleanain, Oisin - Nordgreen, Jan Thomas | Sicilian Defense: Moscow Variation, Main Line | |
| Apr 24, 2026 | Peter Hayes | ½–½ | O`cuilleanain | Round 1: Peter Hayes - O`cuilleanain, Oisin | Torre Attack: Classical Defense | |
| Apr 19, 2026 | Gkavardinas | 1–0 | O`cuilleanain | Round 9: Gkavardinas, Antonios - O`cuilleanain, Oisin | Sicilian Defense: Najdorf Variation, Freak Attack | |
| Apr 15, 2026 | Sofronie | 1–0 | O`cuilleanain | Round 4: Sofronie, Iulian - O`cuilleanain, Oisin | Zukertort Opening | |
| Apr 14, 2026 | Nikolov | 1–0 | O`cuilleanain | Round 2: Nikolov, Momchil - O`cuilleanain, Oisin | Sicilian Defense: Najdorf Variation, Zagreb Variation | |
| Apr 13, 2026 | O`cuilleanain | * | Vuka | Round 1: O`cuilleanain, Oisin - Vuka, Alboreno | ? | |
| Mar 8, 2026 | O`cuilleanain | 0–1 | Melaugh | Round 4: O`cuilleanain, Oisin - Melaugh, Shane | English Opening: Agincourt Defense | |
| Mar 8, 2026 | Bartczak | 0–1 | O`cuilleanain | Round 3: Bartczak, Korneliusz - O`cuilleanain, Oisin | Sicilian Defense: Moscow Variation | |
| Mar 7, 2026 | O`cuilleanain | ½–½ | Artemenko | Round 2: O`cuilleanain, Oisin - Artemenko, Oleg | Sicilian Defense: Accelerated Dragon, Maróczy Bind | |
| Mar 7, 2026 | Bolkeny | 0–1 | O`cuilleanain | Round 1: Bolkeny, Gabor - O`cuilleanain, Oisin | Sicilian Defense: Kronberger Variation | |
| Feb 22, 2026 | Cummins | 0–1 | O`cuilleanain | Round 5: Cummins, Sean - O`cuilleanain, Oisin | Sicilian Defense: Najdorf Variation, English Attack | |
| Feb 22, 2026 | O`cuilleanain | ½–½ | Hushpit | Round 4: O`cuilleanain, Oisin - Hushpit, Lukian | Ruy Lopez: Closed, Martinez Variation | |
| Feb 22, 2026 | Maguire | 0–1 | O`cuilleanain | Round 3: Maguire, Tallann - O`cuilleanain, Oisin | Queen's Gambit Declined: Ragozin Defense, Alekhine Variation | |
| Feb 1, 2026 | O`cuilleanain | 1–0 | O`Gorman | Sligo 2026 Weekender Masters | Sicilian Defense: Najdorf Variation, Zagreb Variation | |
| Feb 1, 2026 | Duggan | 0–1 | O`cuilleanain | Sligo 2026 Weekender Masters | Sicilian Defense: Alapin Variation | |
| Dec 3, 2025 | Hariharan | ½–½ | O`cuilleanain | Round 9: Hariharan, Shambavi - O`cuilleanain, Oisin | King's Indian Defense | |
| Dec 2, 2025 | Gurevich | 0–1 | O`cuilleanain | Round 8: Gurevich, Artjom - O`cuilleanain, Oisin | Bogo-Indian Defense: Retreat Variation | |
| Dec 1, 2025 | O`cuilleanain | 0–1 | Khachatouri | Round 7: O`cuilleanain, Oisin - Khachatouri, Saro | Pirc Defense | |
| Nov 30, 2025 | Farberov | 1–0 | O`cuilleanain | Round 6: Farberov, Maxim - O`cuilleanain, Oisin | Sicilian Defense: Dragon Variation | |
| Nov 30, 2025 | O`cuilleanain | ½–½ | Varney | Round 5: O`cuilleanain, Oisin - Varney, Zoe | Ruy Lopez: Berlin Defense | |
| Nov 29, 2025 | Hng | 0–1 | O`cuilleanain | Round 4: Hng, Mei-En Emmanuelle - O`cuilleanain, Oisin | Sicilian Defense: Alapin Variation, Smith-Morra Declined | |
| Nov 28, 2025 | O`cuilleanain | 0–1 | Schmider | Round 3: O`cuilleanain, Oisin - Schmider, Niklas | Sicilian Defense: Najdorf Variation, Lipnitsky Attack | |
| Nov 28, 2025 | Langheinrich | 1–0 | O`cuilleanain | Round 2: Langheinrich, Ferenc - O`cuilleanain, Oisin | Sicilian Defense: Najdorf Variation, Amsterdam Variation | |
| Nov 27, 2025 | O`cuilleanain | 0–1 | Czopor | Round 1: O`cuilleanain, Oisin - Czopor, Maciej | Sicilian Defense: Nyezhmetdinov-Rossolimo Attack | |
| Jul 16, 2025 | Janeczko | 1–0 | O`cuilleanain | Najdorf Memorial | Sicilian Defense: Closed | |
| Jul 16, 2025 | O`cuilleanain | 1–0 | Swara Lakshmi S Nair | Najdorf Memorial | Sicilian Defense: Najdorf Variation, Lipnitsky Attack | |
| Jul 15, 2025 | Rzeszowski | 0–1 | O`cuilleanain | Najdorf Memorial | Sicilian Defense: Najdorf Variation, Adams Attack | |
| Jul 14, 2025 | O`cuilleanain | 0–1 | Mickiewicz | Najdorf Memorial | Sicilian Defense: Classical Variation, Sozin Attack | |
| Jul 13, 2025 | O`cuilleanain | 0–1 | Salgado Allaria | Najdorf Memorial | Sicilian Defense: Lasker-Pelikan Variation, Sveshnikov Variation, Chelyabinsk Variation | |
| Jul 13, 2025 | Kazmierowski | 0–1 | O`cuilleanain | Najdorf Memorial | Catalan Opening: Closed | |
| Jul 11, 2025 | O`cuilleanain | 1–0 | Golecki | Najdorf Memorial | Sicilian Defense: Nyezhmetdinov-Rossolimo Attack | |
| Jul 10, 2025 | O`cuilleanain | 0–1 | Sengupta | Najdorf Memorial | French Defense: Tarrasch Variation, Closed Variation | |
| Jul 8, 2025 | Golis | 0–1 | O`cuilleanain | Najdorf Memorial | Sicilian Defense: Najdorf Variation | |
| Jun 2, 2025 | Ivanov | 1–0 | O`cuilleanain | Round 6: Ivanov, Andrey A. - O`cuilleanain, Oisin | English Opening: Symmetrical Variation | |
| Jun 2, 2025 | O`cuilleanain | 1–0 | Kholyavko | Round 5: O`cuilleanain, Oisin - Kholyavko, Kirill | Zukertort Opening: Reversed Grünfeld | |
| Jun 1, 2025 | Artemenko | 1–0 | O`cuilleanain | Round 4: Artemenko, Oleg - O`cuilleanain, Oisin | Nimzo-Indian Defense: Three Knights Variation | |
| Jun 1, 2025 | O`cuilleanain | 1–0 | Gallagher | Round 3: O`cuilleanain, Oisin - Gallagher, Brian | Sicilian Defense: Najdorf Variation, Opocensky Variation | |
| May 30, 2025 | O`cuilleanain | 1–0 | Palacios Sanchez | Round 1: O`cuilleanain, Oisin - Palacios Sanchez, Victor | Sicilian Defense: French Variation, Open | |
| May 29, 2025 | Kanyamarala | 1–0 | O`cuilleanain | Round 2: Kanyamarala, Tarun - O`cuilleanain, Oisin | English Opening: Symmetrical Variation, Hedgehog Defense | |
| Apr 21, 2025 | Shriman K | 0–1 | O`cuilleanain | Round 7: Shriman K - O`cuilleanain, Oisin | Old Indian Defense: Normal Variation | |
| Apr 20, 2025 | O`cuilleanain | 1–0 | Kesare | Round 4: O`cuilleanain, Oisin - Kesare, Aarav | Sicilian Defense: Old Sicilian | |
| Apr 20, 2025 | O`cuilleanain | 0–1 | Melaugh | Round 6: O`cuilleanain, Oisin - Melaugh, Shane | Dutch Defense: Classical Variation | |
| Apr 20, 2025 | Ozarpaci | 0–1 | O`cuilleanain | Round 5: Ozarpaci, Mert Can - O`cuilleanain, Oisin | Sicilian Defense: Delayed Alapin Variation, with d6 | |
| Apr 19, 2025 | O`cuilleanain | 1–0 | Voogt | Round 2: O`cuilleanain, Oisin - Voogt, Declan | Ruy Lopez: Open, Classical Defense | |
| Apr 19, 2025 | Holm | 1–0 | O`cuilleanain | Round 3: Holm, Kristian Stuvik - O`cuilleanain, Oisin | Queen's Indian Defense: Petrosian Variation | |
| Apr 18, 2025 | Joe O'Hanlon | 0–1 | O`cuilleanain | Round 1: Joe O'Hanlon - O`cuilleanain, Oisin | Queen's Pawn Game: Barry Attack, Grünfeld Variation | |
| Jan 16, 2025 | O`cuilleanain | 0–1 | Rindhiya V | praha2025 | Italian Game: Classical Variation, Giuoco Pianissimo | |
| Jan 14, 2025 | O`cuilleanain | 0–1 | Topencik | praha2025 | Caro-Kann Defense: Two Knights Attack, Mindeno Variation, Exchange Line | |
| Jun 3, 2024 | O`cuilleanain | ½–½ | Artemenko | Round 6: O`cuilleanain, Oisin - Artemenko, Oleg | Sicilian Defense: Hyperaccelerated Pterodactyl | |
| Jun 3, 2024 | O`cuilleanain | 1–0 | Murphy | Round 5: O`cuilleanain, Oisin - Murphy, Sean J. | English Opening: Anglo-Indian Defense, Anglo-Grünfeld Variation | |
| Jun 2, 2024 | Andrey A. Ivanov | 0–1 | O`cuilleanain | Round 4: Andrey A. Ivanov - O`cuilleanain, Oisin | Sicilian Defense: Kan Variation, Knight Variation | |
| Jun 2, 2024 | O`cuilleanain | * | Collins | Round 3: O`cuilleanain, Oisin - Collins, Adam | King's Indian Attack | |
| Jun 1, 2024 | Flynn | ½–½ | O`cuilleanain | Round 2: Flynn, Jacob - O`cuilleanain, Oisin | Nimzo-Indian Defense: Three Knights Variation | |
| Jun 1, 2024 | O`cuilleanain | 1–0 | Neary | Round 1: O`cuilleanain, Oisin - Neary, Graham | ? | |
| Mar 28, 2024 | Heberla | 1–0 | O`cuilleanain | Grenke Chess Open 2024 | King's Indian Defense: Normal Variation, Rare Defenses | |
| Jul 11, 2023 | Schoeppe | 0–1 | Juracak | Piestany B | King's Pawn Game: MacLeod Attack | |
| Jan 13, 2023 | Ochedzan | 1–0 | O`cuilleanain | Prague Open | Czech Tour | Sicilian Defense: Delayed Alapin Variation, with d6 | |
| Jan 12, 2023 | O`cuilleanain | 1–0 | Krasovskiy | Prague Open | Czech Tour | Catalan Opening: Closed Variation, Traditional Variation | |
| Jan 10, 2023 | O`cuilleanain | * | Tesar | Prague Open | Czech Tour | ? | |
| Jul 19, 2023 | O`cuilleanain Oisin | 0–1 | Kolb Tobias | Open A | Queen's Gambit Declined: Exchange Variation, Positional Variation | |
| Jul 17, 2023 | Kucharska Honorata | 0–1 | O`cuilleanain Oisin | Open A | Ruy Lopez: Morphy Defense, Anderssen Variation | |
| Jul 17, 2023 | Reuker Jari | ½–½ | O`cuilleanain Oisin | Open A | Zukertort Opening | |
| Jul 16, 2023 | O`cuilleanain Oisin | 1–0 | Warchol Kamil | Open A | English Opening: King's English Variation, Four Knights Variation, Flexible Line | |
| Jul 15, 2023 | Pasti Aron | 1–0 | O`cuilleanain Oisin | Open A | Sicilian Defense: Najdorf Variation | |
| Jul 14, 2023 | O`cuilleanain Oisin | 1–0 | Maryasin Boris | Open A | Catalan Opening: Open Defense | |
| Jul 13, 2023 | Shirinyan Daniel | ½–½ | O`cuilleanain Oisin | Open A | Four Knights Game: Scotch Variation Accepted | |
| Jul 12, 2023 | O`cuilleanain Oisin | ½–½ | Arvind Ramnath Iyer | Open A | English Opening: Anglo-Indian Defense, Queen's Knight Variation | |
| Jul 11, 2023 | Jablonicky Martin | 1–0 | O`cuilleanain Oisin | Open A | Sicilian Defense: Moscow Variation | |