| Jun 14, 2025 | Hamann | 1–0 | Classen | DEM U12 2025 | French Defense: Advance Variation, Euwe Variation | |
| Jun 13, 2025 | Classen | 1–0 | Shneider | DEM U12 2025 | Caro-Kann Defense: Two Knights Attack, Mindeno Variation, Exchange Line | |
| Jun 12, 2025 | Brueckner | 1–0 | Classen | DEM U12 2025 | French Defense: Tarrasch Variation, Chistyakov Defense, Modern Line | |
| Jun 11, 2025 | Classen | ½–½ | Ziem | DEM U12 2025 | Ruy Lopez: Closed | |
| Jun 11, 2025 | Krishnan | 1–0 | Classen | DEM U12 2025 | Sicilian Defense: Dragon Variation, Yugoslav Attack, Modern Line | |
| Jun 10, 2025 | Classen | ½–½ | Shalovylo | DEM U12 2025 | French Defense: Steinitz Variation, Boleslavsky Variation | |
| Jun 9, 2025 | Zielke | ½–½ | Classen | DEM U12 2025 | French Defense: Advance Variation, Paulsen Attack | |
| Jun 8, 2025 | Classen | ½–½ | Teng | DEM U12 2025 | Sicilian Defense | |
| Jun 8, 2025 | Retzlaff | ½–½ | Classen | DEM U12 2025 | Sicilian Defense: Dragon Variation, Yugoslav Attack, Modern Line | |
| Apr 17, 2025 | Classen | ½–½ | Nurakyn | Round 8: Classen, Marnin - Nurakyn, Suleiman | Caro-Kann Defense: Two Knights Attack | |
| Apr 17, 2025 | Classen | 0–1 | El Zein | Round 10: Classen, Marnin - El Zein, Bassam | Sicilian Defense: Nimzowitsch Variation, Advance Variation | |
| Apr 17, 2025 | Kolar | ½–½ | Classen | Round 9: Kolar, Edvard - Classen, Marnin | Queen's Pawn Game: Colle System | |
| Apr 16, 2025 | Classen | 0–1 | Guo | Round 1: Classen, Marnin - Guo, Ethan | Nimzo-Indian Defense: Leningrad Variation | |
| Apr 14, 2025 | Braaten | 1–0 | Classen | Round 6: Braaten, Birk - Classen, Marnin | French Defense: Exchange Variation, Monte Carlo Variation | |
| Apr 13, 2025 | Classen | 0–1 | Sason | Round 2: Classen, Marnin - Sason, Noam | Sicilian Defense: Dragon Variation, Yugoslav Attack | |
| Apr 13, 2025 | Classen | 0–1 | Nguyen Truong An Khang | Round 4: Classen, Marnin - Nguyen Truong An Khang | Caro-Kann Defense: Two Knights Attack | |
| Dec 30, 2024 | Tomovski | 0–1 | Classen | DVM U12 2024 | French Defense: Exchange Variation | |
| Dec 29, 2024 | Classen | 1–0 | Buff | DVM U12 2024 | Sicilian Defense: Closed | |
| Dec 28, 2024 | Classen | 0–1 | Fadeev | DVM U12 2024 | Sicilian Defense: Grand Prix Attack | |
| Dec 28, 2024 | Classen | 1–0 | Pflugbeil | DVM U12 2024 | Pirc Defense | |
| Dec 27, 2024 | Classen | 1–0 | Lieberknecht | DVM U12 2024 | Pirc Defense | |
| Dec 27, 2024 | Teng | ½–½ | Classen | DVM U12 2024 | French Defense: Steinitz Variation, Boleslavsky Variation | |
| May 25, 2024 | Classen | 1–0 | Lau | ODJM C 2024 | Grünfeld Defense: Exchange Variation, Classical Variation | |
| May 24, 2024 | Classen | 1–0 | Margaryan | ODJM C 2024 | Queen's Gambit Declined: Harrwitz Attack | |
| May 23, 2024 | Classen | ½–½ | Classen | ODJM C 2024 | Vienna Game: Vienna Gambit | |
| May 22, 2024 | Classen | 0–1 | Schilay | ODJM C 2024 | Italian Game: Hungarian Defense | |
| May 22, 2024 | Lang | ½–½ | Classen | ODJM C 2024 | Queen's Gambit Declined: Modern Variation | |
| May 21, 2024 | Betz | 0–1 | Classen | ODJM C 2024 | Sicilian Defense: Dragon Variation, Classical Variation | |
| May 20, 2024 | Classen | 1–0 | Weibrecht | ODJM C 2024 | King's Indian Defense: Normal Variation, Rare Defenses | |
| May 19, 2024 | Classen | 1–0 | Bharathula | ODJM C 2024 | Ruy Lopez: Closed | |
| May 19, 2024 | Weidenhoefer | 0–1 | Classen | ODJM C 2024 | Queen's Pawn Game: Levitsky Attack | |
| Jun 11, 2022 | Classen | ½–½ | Hellriegel | DEM U10 2022 | Ruy Lopez: Morphy Defense, Neo-Arkhangelsk Variation | |
| Jun 10, 2022 | Classen | 0–1 | Vu | DEM U10 2022 | Ruy Lopez: Closed | |
| Jun 10, 2022 | Wang | 1–0 | Classen | DEM U10 2022 | French Defense: Horwitz Attack, Papa-Ticulat Gambit | |
| Jun 9, 2022 | Svanidze | 0–1 | Classen | DEM U10 2022 | French Defense: Exchange Variation | |
| Jun 8, 2022 | Classen | 1–0 | Leonhardt | DEM U10 2022 | Ruy Lopez: Morphy Defense | |
| Jun 8, 2022 | Wetzig | 0–1 | Classen | DEM U10 2022 | French Defense: Exchange Variation | |
| Jun 7, 2022 | Wolf | 1–0 | Classen | DEM U10 2022 | French Defense: Advance Variation, Paulsen Attack | |
| Jun 6, 2022 | Classen | 1–0 | Mulgunov | DEM U10 2022 | Ruy Lopez: Closed, Trajkovic Counterattack | |
| Jun 6, 2022 | Classen | 0–1 | Li | DEM U10 2022 | Sicilian Defense: Najdorf Variation, Opocensky Variation, Modern Line | |
| Jun 5, 2022 | Classen | 0–1 | Zimmer | DEM U10 2022 | Ruy Lopez: Morphy Defense, Classical Defense Deferred | |
| Jun 5, 2022 | Rodriguez Klasen | 1–0 | Classen | DEM U10 2022 | Zukertort Opening: Queen's Gambit Invitation | |
| — | Classen | 0–1 | Belyaletdinov | Round 2: Classen, Marnin - Belyaletdinov, Leonard | Caro-Kann Defense: Two Knights Attack | |
| — | Classen | 0–1 | Stergioulas | Round 2: Classen, Marnin - Stergioulas, Vasilis | Scandinavian Defense: Main Line, Mieses Variation | |
| — | Classen | ½–½ | Kavkasidze | Round 5: Classen, Marnin - Kavkasidze, Ilia | Sicilian Defense: Katalimov Variation | |
| — | Classen | 0–1 | Zhang | Round 6: Classen, Marnin - Zhang, Jingran | Caro-Kann Defense: Two Knights Attack | |
| — | Classen | 0–1 | Baghramyan | Round 9: Classen, Marnin - Baghramyan, Sofia | Sicilian Defense: Kan Variation, Modern Variation | |
| — | Tretiak | 1–0 | Classen | Round 1: Tretiak, Igor - Classen, Marnin | French Defense: King's Indian Attack | |
| — | Belyaletdinov | 1–0 | Classen | Round 1: Belyaletdinov, Leonard - Classen, Marnin | French Defense: Exchange Variation | |
| — | Toktas | 1–0 | Classen | Round 7: Toktas, Cagan - Classen, Marnin | Sicilian Defense: Chekhover Variation | |