| May 25, 2026 | Decoster | 0–1 | Kazarjan | Round 7: Decoster, Frederic - Kazarjan, Gachatur | Sicilian Defense: Dragon Variation | |
| May 25, 2026 | Guliyev | 1–0 | Decoster | Round 6: Guliyev, Namig - Decoster, Frederic | Sicilian Defense: Four Knights Variation | |
| May 24, 2026 | Decoster | ½–½ | Dann | Round 5: Decoster, Frederic - Dann, Matthias | Sicilian Defense: Najdorf Variation | |
| May 24, 2026 | De Winter | 0–1 | Decoster | Round 4: De Winter, Arthur - Decoster, Frederic | Queen's Gambit Declined: Exchange Variation, Positional Variation | |
| May 23, 2026 | Decoster | * | De Rycke | Round 3: Decoster, Frederic - De Rycke, Tyani | ? | |
| May 23, 2026 | Fokkinga | * | Decoster | Round 2: Fokkinga, Tijl - Decoster, Frederic | ? | |
| May 22, 2026 | Decoster | * | Roebers | Round 1: Decoster, Frederic - Roebers, Jan | ? | |
| May 9, 2026 | Fedorchuk | 1–0 | Decoster | Luc Winants Memorial Rapid Chess Tournament 2026 | Sicilian Defense: Kan Variation | |
| Oct 25, 2025 | Decoster | 0–1 | Ziegler | Round 7: Decoster, Frederic - Ziegler, Ari | Sicilian Defense: Lasker-Pelikan Variation | |
| Oct 22, 2025 | Bochnicka | 1–0 | Decoster | Round 4: Bochnicka, Vladimir - Decoster, Frederic | Sicilian Defense: Kan Variation, Polugaevsky Variation | |
| Oct 20, 2025 | Decoster | ½–½ | Sirin | Round 2: Decoster, Frederic - Sirin, Atakan | Sicilian Defense: Dragon Variation, Yugoslav Attack | |
| Oct 25, 2024 | Jablonicky | 0–1 | Decoster | 39th European Chess Club Cup | Grünfeld Defense: Three Knights Variation, Burille Variation | |
| Oct 24, 2024 | Decoster | 1–0 | Kukk | 39th European Chess Club Cup | Modern Defense | |
| Oct 22, 2024 | Decoster | ½–½ | Pacher | 39th European Chess Club Cup | Caro-Kann Defense: Tartakower Variation | |
| Oct 21, 2024 | Rozen | ½–½ | Decoster | 39th European Chess Club Cup | Grünfeld Defense: Exchange Variation, Modern Exchange Variation | |
| Oct 20, 2024 | Decoster | 1–0 | Blazquez Sanz | 39th European Chess Club Cup | French Defense: Winawer Variation, Alekhine Gambit, Kan Variation | |
| Oct 23, 2024 | Stocek | 1–0 | Decoster | Round 4: Stocek, Jiri - Decoster, Frederic | Sicilian Defense: Dragon Variation | |
| Oct 1, 2023 | Pechac | 1–0 | Decoster | European Chess Club Cup 2023 | English Opening: Symmetrical Variation, Four Knights Variation | |
| May 28, 2023 | Decoster | * | Weller | Limburg Open | ? | |
| May 28, 2023 | De Boer | * | Decoster | Limburg Open | ? | |
| Oct 8, 2022 | Decoster | 0–1 | Gorshtein | ECCC_22 | Sicilian Defense: Lasker-Pelikan Variation, Sveshnikov Variation | |
| Oct 6, 2022 | Neugebauer | 1–0 | Decoster | ECCC_22 | Italian Game: Classical Variation, Giuoco Pianissimo, with d6 | |
