| May 17, 2026 | Braeutigam | ½–½ | Schmitzer | Runde 7: Braeutigam, Alexander - Schmitzer, Klaus | Horwitz Defense | |
| May 16, 2026 | Braeutigam | 0–1 | Schmitzer | Runde 6: Braeutigam, Katerina - Schmitzer, Klaus | Caro-Kann Defense: Advance Variation | |
| May 16, 2026 | Schmitzer | 1–0 | Bub | Runde 5: Schmitzer, Klaus - Bub, Volker | Pirc Defense | |
| May 15, 2026 | Schmitzer | 0–1 | Carlstedt | Runde 4: Schmitzer, Klaus - Carlstedt, Jonathan | Trompowsky Attack | |
| May 15, 2026 | Hansen | 0–1 | Schmitzer | Runde 3: Hansen, Peter - Schmitzer, Klaus | Caro-Kann Defense | |
| May 14, 2026 | Schmitzer | 1–0 | Meschke | Runde 2: Schmitzer, Klaus - Meschke, Oliver | Sicilian Defense: Accelerated Dragon, Modern Variation | |
| May 14, 2026 | Solar | 0–1 | Schmitzer | Round 1: Solar, Mavi - Schmitzer, Klaus | Caro-Kann Defense: Two Knights Attack | |
| Dec 19, 2025 | Schmitzer | ½–½ | Gluma | Round 2: Schmitzer, Klaus - Gluma, Christian | Modern Defense: Standard Line | |
| Nov 21, 2025 | Schmitzer | 0–1 | Smith | Heusenstamm Sparkassen Open 2025 | Sicilian Defense: Richter-Rauzer Variation, Modern Variation | |
| Oct 18, 2025 | Schmitzer | 0–1 | Schwitkowski | Runde 9: Schmitzer, Klaus - Schwitkowski, Luka | Sicilian Defense: Scheveningen Variation, English Attack, with f3 | |
| Oct 17, 2025 | Poetsch | 1–0 | Schmitzer | Runde 8: Poetsch, Hagen - Schmitzer, Klaus | Caro-Kann Defense: Advance Variation, Short Variation | |
| Oct 16, 2025 | Schmitzer | ½–½ | Winkler | Runde 7: Schmitzer, Klaus - Winkler, Yonathan | Queen's Pawn Game: Levitsky Attack | |
| Oct 15, 2025 | Schulte | 0–1 | Schmitzer | Runde 6: Schulte, Tobias - Schmitzer, Klaus | Caro-Kann Defense: Advance Variation, Tal Variation | |
| Oct 13, 2025 | Schmitzer | 1–0 | Schwarz | Runde 4: Schmitzer, Klaus - Schwarz, David | Four Knights Game: Glek System | |
| Oct 12, 2025 | Chua | 0–1 | Schmitzer | Runde 3: Chua, Ethan - Schmitzer, Klaus | Caro-Kann Defense: Tartakower Variation | |
| Oct 12, 2025 | Schmitzer | 1–0 | Pfaar | Runde 2: Schmitzer, Klaus - Pfaar, Zeno | Trompowsky Attack | |
| Oct 11, 2025 | Jansen | 0–1 | Schmitzer | Runde 1: Jansen, Dirk - Schmitzer, Klaus | English Opening | |
| Oct 11, 2025 | Schmitzer | 0–1 | Liu | Runde 5: Schmitzer, Klaus - Liu, Yi | French Defense: Tarrasch Variation, Open System, Main Line | |
| Mar 29, 2025 | Schmitzer | 1–0 | Miller | NRW-Blitz-Einzelmeisterschaft 2025 | Nimzowitsch Defense: Scandinavian Variation, Bogoljubow Variation | |
| Mar 29, 2025 | Schmitzer | 1–0 | Schneider | NRW-Blitz-Einzelmeisterschaft 2025 | Modern Defense: Standard Line | |
| Mar 29, 2025 | Schmitzer | 0–1 | Moeller | NRW-Blitz-Einzelmeisterschaft 2025 | Sicilian Defense: Four Knights Variation, Exchange Variation | |
| Mar 29, 2025 | Schmitzer | ½–½ | Schulze | NRW-Blitz-Einzelmeisterschaft 2025 | Caro-Kann Defense: Advance Variation, Botvinnik-Carls Defense | |
| Mar 29, 2025 | Schmitzer | 1–0 | Nhan | NRW-Blitz-Einzelmeisterschaft 2025 | Caro-Kann Defense: Panov Attack, Modern Defense | |
| Mar 29, 2025 | Gallas | ½–½ | Schmitzer | NRW-Blitz-Einzelmeisterschaft 2025 | Horwitz Defense | |
| Mar 29, 2025 | Strehse | 1–0 | Schmitzer | NRW-Blitz-Einzelmeisterschaft 2025 | Caro-Kann Defense: Two Knights Attack | |
| Mar 29, 2025 | Breitkopf-Lazar | 1–0 | Schmitzer | NRW-Blitz-Einzelmeisterschaft 2025 | Caro-Kann Defense: Bronstein-Larsen Variation | |
| Mar 29, 2025 | Stricker | 1–0 | Schmitzer | NRW-Blitz-Einzelmeisterschaft 2025 | Caro-Kann Defense: Advance Variation, Tal Variation | |
| Oct 19, 2024 | Schmitzer | 1–0 | Winkler | Round 9: Schmitzer, Klaus - Winkler, Yonathan | Sicilian Defense: Kan Variation, Wing Attack | |
| Oct 18, 2024 | Naveen Kumar P | ½–½ | Schmitzer | Round 8: Naveen Kumar P - Schmitzer, Klaus | English Defense | |
| Oct 15, 2024 | Michalczak | 0–1 | Schmitzer | Round 5: Michalczak, Thomas - Schmitzer, Klaus | Caro-Kann Defense: Advance Variation, Tal Variation | |
| Oct 14, 2024 | Schmitzer | 1–0 | Heidemann | Round 4: Schmitzer, Klaus - Heidemann, Kristjan | Trompowsky Attack | |
| Oct 13, 2024 | Mueller | ½–½ | Schmitzer | Round 3: Mueller, Konstantin - Schmitzer, Klaus | Caro-Kann Defense: Exchange Variation | |
| Oct 13, 2024 | Schmitzer | 1–0 | Mueller | Round 2: Schmitzer, Klaus - Mueller, Frank | Sicilian Defense: Taimanov Variation, Bastrikov Variation, English Attack | |
| Oct 12, 2024 | Neumann | 0–1 | Schmitzer | Round 1: Neumann, Theodor - Schmitzer, Klaus | Caro-Kann Defense: Advance Variation, Bronstein Variation | |
| Oct 11, 2024 | Schmitzer | 0–1 | Korchynskyi | Round 7: Schmitzer, Klaus - Korchynskyi, Mykola | Caro-Kann Defense: Exchange Variation | |
| Oct 11, 2024 | Schmitzer | 1–0 | Bilovil | Round 6: Schmitzer, Klaus - Bilovil, Bogdan | French Defense: Tarrasch Variation, Chistyakov Defense | |
| May 28, 2023 | Schmitzer | * | Maatman | Limburg Open | ? | |
| May 28, 2023 | Smeets | * | Schmitzer | Limburg Open | ? | |
