| Dec 3, 2023 | Teodor-Cosmin Nedelcu | 0–1 | Mihnea Costachi | Round 8: Teodor-Cosmin Nedelcu - Mihnea Costachi | King's Indian Defense: Kramer Variation | |
| Dec 3, 2023 | Mihnea Costachi | 1–0 | Lucian-Costin Miron | Round 7: Mihnea Costachi - Lucian-Costin Miron | Bogo-Indian Defense: Nimzowitsch Variation | |
| Dec 3, 2023 | Mihnea Costachi | 1–0 | Costica-Ciprian Nanu | Round 6: Mihnea Costachi - Costica-Ciprian Nanu | Queen's Indian Defense: Fianchetto Variation, Kramnik Variation | |
| Dec 3, 2023 | Romulus-Cristian Stefan | 0–1 | Mihnea Costachi | Round 5: Romulus-Cristian Stefan - Mihnea Costachi | King's Indian Defense: Smyslov Variation | |
| Dec 3, 2023 | Mihnea Costachi | ½–½ | Robert-Ionut Creanga | Round 4: Mihnea Costachi - Robert-Ionut Creanga | Queen's Gambit Declined: Three Knights Variation | |
| Dec 3, 2023 | Constantin Lupulescu | ½–½ | Mihnea Costachi | Round 3: Constantin Lupulescu - Mihnea Costachi | King's Indian Defense: Semi-Averbakh System | |
| Dec 3, 2023 | Mihnea Costachi | 1–0 | Alexandru-Ioan Simina | Round 2: Mihnea Costachi - Alexandru-Ioan Simina | Italian Game: Evans Gambit, Mieses Defense | |
| Dec 3, 2023 | Razvan-Andrei Burja-Udrea | 0–1 | Mihnea Costachi | Round 1: Razvan-Andrei Burja-Udrea - Mihnea Costachi | Italian Game: Classical Variation, Greco Gambit | |
| Dec 2, 2023 | Mihnea Costachi | 1–0 | Daniel-Cristian Padurean | Round 8: Mihnea Costachi - Daniel-Cristian Padurean | Queen's Pawn Game: Chigorin Variation | |
| Dec 2, 2023 | Teodor-Cosmin Nedelcu | 1–0 | Mihnea Costachi | Round 7: Teodor-Cosmin Nedelcu - Mihnea Costachi | Slav Defense: Exchange Variation | |
| Dec 2, 2023 | Mihnea Costachi | ½–½ | Andrei Negrean | Round 6: Mihnea Costachi - Andrei Negrean | Rapport-Jobava System | |
| Dec 2, 2023 | Lucian-Costin Miron | ½–½ | Mihnea Costachi | Round 5: Lucian-Costin Miron - Mihnea Costachi | English Opening: Anglo-Indian Defense, King's Knight Variation | |
| Dec 2, 2023 | Nicolae Dicu | 0–1 | Mihnea Costachi | Round 2: Nicolae Dicu - Mihnea Costachi | King's Indian Defense: Makogonov Variation | |
| Dec 2, 2023 | Mihnea Costachi | 1–0 | Romulus-Cristian Stefan | Round 1: Mihnea Costachi - Romulus-Cristian Stefan | Slav Defense: Schlechter Variation | |
| Dec 2, 2023 | Mihnea Costachi | 0–1 | Constantin Lupulescu | Round 4: Mihnea Costachi - Constantin Lupulescu | Queen's Gambit Declined: Ragozin Defense | |
| Dec 2, 2023 | Mihnea Costachi | ½–½ | Costica-Ciprian Nanu | Round 3: Mihnea Costachi - Costica-Ciprian Nanu | Queen's Indian Defense: Fianchetto Variation, Kramnik Variation | |
| Dec 1, 2023 | Mihnea Costachi | ½–½ | Filip Magold | Round 10: Mihnea Costachi - Filip Magold | Queen's Gambit Accepted: Classical Defense, Steinitz Variation, Exchange Variation | |
| Dec 1, 2023 | Vlad-Cristian Jianu | 0–1 | Mihnea Costachi | Round 9: Vlad-Cristian Jianu - Mihnea Costachi | King's Indian Defense: Makogonov Variation | |
| Dec 1, 2023 | Teodor-Cosmin Nedelcu | 0–1 | Mihnea Costachi | Round 8: Teodor-Cosmin Nedelcu - Mihnea Costachi | King's Indian Defense: Kramer Variation | |
| Dec 1, 2023 | Mihnea Costachi | 1–0 | David Gavrilescu | Round 7: Mihnea Costachi - David Gavrilescu | Queen's Gambit Declined: Barmen Variation | |
| Dec 1, 2023 | Mihnea Costachi | 1–0 | Armand Veress | Round 6: Mihnea Costachi - Armand Veress | Tarrasch Defense: Dubov Tarrasch | |
| Dec 1, 2023 | Costica-Ciprian Nanu | 0–1 | Mihnea Costachi | Round 5: Costica-Ciprian Nanu - Mihnea Costachi | King's Indian Defense: Fianchetto Variation, Lesser Simagin (Spassky) | |
| Dec 1, 2023 | Mihnea Costachi | 0–1 | Constantin Lupulescu | Round 4: Mihnea Costachi - Constantin Lupulescu | Queen's Gambit Declined: Barmen Variation | |
| Dec 1, 2023 | Teodor-Mihnea Voicu | 0–1 | Mihnea Costachi | Round 3: Teodor-Mihnea Voicu - Mihnea Costachi | King's Indian Defense: Orthodox Variation, Glek Defense | |
| Dec 1, 2023 | Mihnea Costachi | 1–0 | David Cordea | Round 2: Mihnea Costachi - David Cordea | Queen's Gambit Accepted: Normal Variation, Traditional System | |
| Dec 1, 2023 | Iulia-Cristiana Stefan | 0–1 | Mihnea Costachi | Round 1: Iulia-Cristiana Stefan - Mihnea Costachi | King's Indian Defense: Normal Variation, King's Knight Variation | |
| Nov 5, 2023 | Mihnea Costachi | 1–0 | Marius Manolache | Round 10: Mihnea Costachi - Marius Manolache | Mexican Defense | |
| Nov 5, 2023 | Anna Zatonskih | 0–1 | Mihnea Costachi | Round 9: Anna Zatonskih - Mihnea Costachi | East Indian Defense | |
| Nov 5, 2023 | Mihnea Costachi | 1–0 | Anastasiya Rakhmangulova | Round 8: Mihnea Costachi - Anastasiya Rakhmangulova | Semi-Slav Defense: Stoltz Variation, Shabalov Attack | |
| Nov 5, 2023 | Vladimir-Alexandru Cnejev | ½–½ | Mihnea Costachi | Round 7: Vladimir-Alexandru Cnejev - Mihnea Costachi | Ruy Lopez: Closed | |
| Nov 5, 2023 | Mihnea Costachi | 1–0 | Gheorghe Grad | Round 6: Mihnea Costachi - Gheorghe Grad | Vienna Game: Stanley Variation | |
| Nov 5, 2023 | Alexandru Sachilaru | ½–½ | Mihnea Costachi | Round 5: Alexandru Sachilaru - Mihnea Costachi | Ruy Lopez: Morphy Defense, Bayreuth Variation | |
| Nov 4, 2023 | Mihnea Costachi | ½–½ | Andrei Negrean | Round 4: Mihnea Costachi - Andrei Negrean | Caro-Kann Defense: Panov Attack, Main Line | |
| Nov 4, 2023 | Sasha-Matei Craciun | ½–½ | Mihnea Costachi | Round 3: Sasha-Matei Craciun - Mihnea Costachi | Ruy Lopez: Morphy Defense, Modern Steinitz Defense | |
| Nov 4, 2023 | Mihnea Costachi | 1–0 | Marian Zaim | Round 2: Mihnea Costachi - Marian Zaim | Van Geet Opening | |
| Nov 4, 2023 | Denis-Gabriel Grasu | 0–1 | Mihnea Costachi | Round 1: Denis-Gabriel Grasu - Mihnea Costachi | King's Gambit Declined: Classical Variation | |
| Aug 6, 2023 | Mihnea Costachi | * | Mihaela Sandu | Round 10: Mihnea Costachi - Mihaela Sandu | ? | |
| Aug 6, 2023 | Mihnea Costachi | 0–1 | Mihnea-Ionut Ognean | Round 8: Mihnea Costachi - Mihnea-Ionut Ognean | Rapport-Jobava System | |
| Aug 6, 2023 | Haik M. Martirosyan | 1–0 | Mihnea Costachi | Round 7: Haik M. Martirosyan - Mihnea Costachi | Slav Defense: Chebanenko Variation, Advance System | |
| Aug 6, 2023 | Mihnea Costachi | * | Andreea Navrotescu | Round 6: Mihnea Costachi - Andreea Navrotescu | ? | |
| Aug 6, 2023 | Mihnea Costachi | 1–0 | Evelyn Wagenschuetz | Round 5: Mihnea Costachi - Evelyn Wagenschuetz | Vienna Game: Stanley Variation, Reversed Spanish | |
| Aug 5, 2023 | Constantin Lupulescu | ½–½ | Mihnea Costachi | Round 4: Constantin Lupulescu - Mihnea Costachi | Slav Defense: Quiet Variation, Pin Defense | |
| Apr 30, 2023 | Raunak Sadhwani | 1–0 | Mihnea Costachi | Round 10: Raunak Sadhwani - Mihnea Costachi | King's Indian Defense: Orthodox Variation, Glek Defense | |
| Apr 30, 2023 | Mihnea Costachi | 1–0 | Jakub Roubalik | Round 9: Mihnea Costachi - Jakub Roubalik | Queen's Gambit Declined: Three Knights Variation | |
| Apr 30, 2023 | Nicodim-Cosmin Stepanencu | 0–1 | Mihnea Costachi | Round 8: Nicodim-Cosmin Stepanencu - Mihnea Costachi | Petrov's Defense: Classical Attack, Staunton Variation | |
| Apr 30, 2023 | Mihnea Costachi | 1–0 | Dragos-Nicolae Dumitrache | Round 7: Mihnea Costachi - Dragos-Nicolae Dumitrache | Benko Gambit | |
| Apr 30, 2023 | Filip Magold | 1–0 | Mihnea Costachi | Round 6: Filip Magold - Mihnea Costachi | King's Indian Defense: Normal Variation, Rare Defenses | |
| Apr 30, 2023 | Mihnea Costachi | 1–0 | Silvia-Raluca Sgircea | Round 5: Mihnea Costachi - Silvia-Raluca Sgircea | Queen's Gambit Accepted: Classical Defense, Russian Gambit | |
| Apr 29, 2023 | Cristian-Clement Daianu | ½–½ | Mihnea Costachi | Round 4: Cristian-Clement Daianu - Mihnea Costachi | Italian Game: Classical Variation, Giuoco Pianissimo, with a6 | |
| Apr 29, 2023 | Mihnea Costachi | ½–½ | Mihai-Edward Padurariu | Round 3: Mihnea Costachi - Mihai-Edward Padurariu | Tarrasch Defense: Dubov Tarrasch | |
| Apr 29, 2023 | Ema Obada | 0–1 | Mihnea Costachi | Round 2: Ema Obada - Mihnea Costachi | Four Knights Game: Scotch Variation Accepted | |
| Apr 29, 2023 | Mihnea Costachi | 1–0 | Ionel Linca | Round 1: Mihnea Costachi - Ionel Linca | Van Geet Opening | |
| Dec 4, 2022 | Ruslan Soltanici | ½–½ | Mihnea Costachi | Round 7: Ruslan Soltanici - Mihnea Costachi | Ruy Lopez: Morphy Defense, Modern Steinitz Defense | |
| Dec 4, 2022 | Alexandru-Vasile David | ½–½ | Mihnea Costachi | Round 3: Alexandru-Vasile David - Mihnea Costachi | London System | |
| Dec 3, 2022 | Gergely-Andras-Gyula Szabo | ½–½ | Mihnea Costachi | Round 8: Gergely-Andras-Gyula Szabo - Mihnea Costachi | Modern Defense: Standard Defense | |
| Dec 3, 2022 | Mihnea Costachi | 1–0 | Romulus-Cristian Stefan | Round 8: Mihnea Costachi - Romulus-Cristian Stefan | Queen's Pawn Game | |
| Dec 3, 2022 | Mihnea Costachi | ½–½ | Constantin Lupulescu | Round 6: Mihnea Costachi - Constantin Lupulescu | Queen's Gambit Declined: Barmen Variation | |
| Dec 3, 2022 | Robert-Paul Nastase | 0–1 | Mihnea Costachi | Round 5: Robert-Paul Nastase - Mihnea Costachi | Petrov's Defense: Classical Attack, Marshall Variation | |
| Dec 3, 2022 | Mihnea Costachi | 1–0 | Robin-Alexandru Dragomirescu | Round 4: Mihnea Costachi - Robin-Alexandru Dragomirescu | Queen's Indian Defense: Fianchetto Variation, Nimzowitsch Variation | |
| Dec 3, 2022 | Mihnea Costachi | 1–0 | Romulus-Cristian Stefan | Round 2: Mihnea Costachi - Romulus-Cristian Stefan | Modern Defense: Kotov Variation | |
| Dec 3, 2022 | Razvan Teodorescu | 0–1 | Mihnea Costachi | Round 1: Razvan Teodorescu - Mihnea Costachi | King's Indian Defense: Sämisch Variation, Sämisch Gambit | |
| Dec 2, 2022 | Alexandru Manea | ½–½ | Mihnea Costachi | Round 7: Alexandru Manea - Mihnea Costachi | King's Indian Defense: Fianchetto Variation, Lesser Simagin (Spassky) | |
| Dec 2, 2022 | Mihnea Costachi | 1–0 | Lehel Vrencian | Round 6: Mihnea Costachi - Lehel Vrencian | Old Indian Defense | |
| Dec 2, 2022 | Robert-Paul Nastase | ½–½ | Mihnea Costachi | Round 5: Robert-Paul Nastase - Mihnea Costachi | King's Gambit Accepted: Schallopp Defense | |
| Dec 2, 2022 | Mihnea Costachi | 1–0 | Cristian-Daniel Oltean | Round 2: Mihnea Costachi - Cristian-Daniel Oltean | Tarrasch Defense: Dubov Tarrasch | |
| Dec 2, 2022 | Mihnea Costachi | ½–½ | Ioan Cosma | Round 4: Mihnea Costachi - Ioan Cosma | Kangaroo Defense | |
| Dec 2, 2022 | Andrei Filip | ½–½ | Mihnea Costachi | Round 3: Andrei Filip - Mihnea Costachi | Italian Game: Classical Variation, Giuoco Pianissimo, with d6 | |
| Dec 2, 2022 | Ioan-Radu Dima | 0–1 | Mihnea Costachi | Round 1: Ioan-Radu Dima - Mihnea Costachi | Indian Defense: King's Indian Variation, Fianchetto Variation | |
| Nov 6, 2022 | Paulius Pultinevicius | ½–½ | Mihnea Costachi | Round 10: Paulius Pultinevicius - Mihnea Costachi | Slav Defense: Chebanenko Variation | |
| Nov 6, 2022 | Mihnea Costachi | 1–0 | Nadya Toncheva | Round 9: Mihnea Costachi - Nadya Toncheva | Queen's Gambit Accepted: Janowski-Larsen Variation | |
| Nov 6, 2022 | Evgeniya Doluhanova | ½–½ | Mihnea Costachi | Round 8: Evgeniya Doluhanova - Mihnea Costachi | King's Indian Attack: Symmetrical Defense | |
| Nov 6, 2022 | Mihnea Costachi | 1–0 | Marina Makropoulou | Round 7: Mihnea Costachi - Marina Makropoulou | Queen's Gambit Declined: Modern Variation, Normal Line | |
| Nov 6, 2022 | David Navara | 1–0 | Mihnea Costachi | Round 6: David Navara - Mihnea Costachi | King's Indian Defense: Orthodox Variation, Glek Defense | |
| Nov 6, 2022 | Mihnea Costachi | 1–0 | Elena-Luminita Cosma | Round 5: Mihnea Costachi - Elena-Luminita Cosma | Queen's Gambit Declined: Exchange Variation, Positional Variation | |
| Nov 5, 2022 | Athanasios Mastrovasilis | 1–0 | Mihnea Costachi | Round 4: Athanasios Mastrovasilis - Mihnea Costachi | Slav Indian | |
| Nov 5, 2022 | Mihnea Costachi | ½–½ | Vitaliy Bernadskiy | Round 3: Mihnea Costachi - Vitaliy Bernadskiy | Queen's Gambit Declined: Exchange Variation, Positional Variation | |
| Nov 5, 2022 | Iosif Ciocani | 0–1 | Mihnea Costachi | Round 2: Iosif Ciocani - Mihnea Costachi | Italian Game: Classical Variation, Giuoco Pianissimo, with d6 | |
| Nov 5, 2022 | Mihnea Costachi | 1–0 | Iustin Toma | Round 1: Mihnea Costachi - Iustin Toma | Tarrasch Defense: Prague Variation | |
| Sep 29, 2022 | Mihnea Costachi | 1–0 | Alin-Mile Berescu | Round 9: Mihnea Costachi - Alin-Mile Berescu | Queen's Gambit Accepted: Classical Defense, Rubinstein Variation | |
| Sep 28, 2022 | Dragos-Andrei Antonica | ½–½ | Mihnea Costachi | Round 8: Dragos-Andrei Antonica - Mihnea Costachi | Torre Attack: Fianchetto Defense | |
| Sep 27, 2022 | Mihnea Costachi | ½–½ | George Stoleriu | Round 7: Mihnea Costachi - George Stoleriu | Indian Defense: Przepiorka Variation | |
| Sep 27, 2022 | Iustin Ciorgovean | 0–1 | Mihnea Costachi | Round 1: Iustin Ciorgovean - Mihnea Costachi | Slav Indian | |
| Sep 27, 2022 | Tudor-Alexandru Ursente | 0–1 | Mihnea Costachi | Round 2: Tudor-Alexandru Ursente - Mihnea Costachi | English Opening: Anglo-Indian Defense, Queen's Knight Variation | |
| Sep 27, 2022 | Mihnea Costachi | 1–0 | Iulian Barzanu | Round 5: Mihnea Costachi - Iulian Barzanu | Queen's Pawn Game | |
| Sep 27, 2022 | Robert-Daniel Pisu | ½–½ | Mihnea Costachi | Round 6: Robert-Daniel Pisu - Mihnea Costachi | Ruy Lopez: Cozio Defense | |
| Sep 27, 2022 | Hunor-Zoltan Antal | 0–1 | Mihnea Costachi | Round 4: Hunor-Zoltan Antal - Mihnea Costachi | Ruy Lopez: Morphy Defense, Cozio Defense | |
| Aug 28, 2022 | Mihnea Costachi | 1–0 | Ori Kobo | Round 9: Mihnea Costachi - Ori Kobo | Queen's Gambit Declined: Vienna Variation, Quiet Variation | |
| Aug 27, 2022 | Samuel-Timotei Ghimpu | 0–1 | Mihnea Costachi | Round 8: Samuel-Timotei Ghimpu - Mihnea Costachi | Italian Game: Two Knights Defense, Polerio Defense, Bishop Check Line | |
| Aug 26, 2022 | Mihnea Costachi | ½–½ | Alberto David | Round 7: Mihnea Costachi - Alberto David | Semi-Slav Defense: Chigorin Defense | |
| Aug 25, 2022 | Olexiy Bilych | ½–½ | Mihnea Costachi | Round 6: Olexiy Bilych - Mihnea Costachi | Ruy Lopez: Closed, Anti-Marshall | |
| Aug 24, 2022 | Mihnea Costachi | ½–½ | Gellert Karacsonyi | Round 5: Mihnea Costachi - Gellert Karacsonyi | English Opening: Symmetrical Variation, Botvinnik System Reversed, with Nf3 | |
| Aug 23, 2022 | Mircea Talu | 0–1 | Mihnea Costachi | Round 4: Mircea Talu - Mihnea Costachi | Slav Defense: Chebanenko Variation | |
| Aug 22, 2022 | Mihnea Costachi | 1–0 | Almos Konyves | Round 3: Mihnea Costachi - Almos Konyves | Indian Defense: London System | |
| Aug 21, 2022 | Balazs Pasztor | 1–0 | Mihnea Costachi | Round 2: Balazs Pasztor - Mihnea Costachi | Ruy Lopez: Closed | |
| Aug 21, 2022 | Mihnea Costachi | 1–0 | Armand Veress | Round 1: Mihnea Costachi - Armand Veress | Queen's Pawn Game: Zukertort Variation | |