| May 24, 2026 | Simenon | 1–0 | Den Hartog | Round 13: Simenon, Jozef - Den Hartog, Marijn | Polish Opening | |
| May 24, 2026 | Den Hartog | 0–1 | Kamphuis | Round 12: Den Hartog, Marijn - Kamphuis, Jasper | Vienna Game: Mieses Variation | |
| May 24, 2026 | Terlouw | 1–0 | Den Hartog | Round 11: Terlouw, Wouter - Den Hartog, Marijn | Queen's Gambit Declined: Janowski Variation | |
| May 24, 2026 | Den Hartog | 0–1 | Van der Werf | Round 10: Den Hartog, Marijn - Van der Werf, Mark | Mieses Opening | |
| May 24, 2026 | Den Hartog | 0–1 | Ootes | Round 8: Den Hartog, Marijn - Ootes, Lars | Pirc Defense | |
| May 24, 2026 | Slagboom | 0–1 | Den Hartog | Round 9: Slagboom, Leandro - Den Hartog, Marijn | French Defense: Rubinstein Variation, Kasparov Attack | |
| May 23, 2026 | Grooten | 0–1 | Den Hartog | Round 5: Grooten, Tommy - Den Hartog, Marijn | Queen's Gambit Declined: Janowski Variation | |
| May 23, 2026 | De Boer | 0–1 | Den Hartog | Round 7: De Boer, Eelke - Den Hartog, Marijn | French Defense: Advance Variation, Euwe Variation | |
| May 23, 2026 | Den Hartog | 1–0 | Jellema | Round 6: Den Hartog, Marijn - Jellema, Pieter | Caro-Kann Defense: Endgame Variation | |
| May 23, 2026 | Aravindhan | ½–½ | Den Hartog | Round 4: Aravindhan, Achyuth - Den Hartog, Marijn | Caro-Kann Defense | |
| May 23, 2026 | Den Hartog | 0–1 | Grochal | Round 3: Den Hartog, Marijn - Grochal, Joey | Van Geet Opening | |
| May 23, 2026 | Bekker | ½–½ | Den Hartog | Round 2: Bekker, Stefan - Den Hartog, Marijn | English Opening: Agincourt Defense, Bogoljubow Defense | |
| May 23, 2026 | Den Hartog | 1–0 | Pel | Round 1: Den Hartog, Marijn - Pel, Bonno | Zukertort Opening: Kingside Fianchetto | |
| Jun 6, 2025 | Den Hartog | 0–1 | Dann | Round 1: Den Hartog, Marijn - Dann, Matthias | Sicilian Defense: Keres Variation | |
| Apr 18, 2025 | Roshka | 1–0 | Den Hartog | Round 2: Roshka, Yevgeniy - Den Hartog, Marijn | Bogo-Indian Defense: Retreat Variation | |