| Jan 4, 2026 | Kristofer Kais | 1–0 | Leht | Round 5: Kristofer Kais - Leht, Karl Samuel | Queen's Pawn Game: Colle System | |
| Jan 3, 2026 | Leht | 1–0 | Istratova | Round 4: Leht, Karl Samuel - Istratova, Nika | Italian Game: Classical Variation, Greco Gambit, Anderssen Variation | |
| Jan 2, 2026 | Leht | 0–1 | Kibe | Round 2: Leht, Karl Samuel - Kibe, Marten | Indian Defense: London System | |
| Jan 2, 2026 | Kojus | 0–1 | Leht | Round 1: Kojus, Lukas - Leht, Karl Samuel | Italian Game: Scotch Gambit, Double Gambit Accepted | |
| Oct 29, 2025 | Leht | 0–1 | Uzdemir | Round 1: Leht, Karl Samuel - Uzdemir, Ali Poyraz | Sicilian Defense: Sozin Attack, Main Line | |
| Apr 28, 2024 | Leht | 0–1 | Kleimenov | Round 1: Leht, Karl Samuel - Kleimenov, Nikolay | Sicilian Defense: Najdorf Variation | |
| Apr 27, 2024 | Leht | 0–1 | Hanache | Round 6: Leht, Karl Samuel - Hanache, Kai | Sicilian Defense: Classical Variation | |
| Nov 26, 2024 | Vorobyov | 1–0 | Leht | Round 11: Vorobyov, Radmir - Leht, Karl Samuel | Dutch Defense: Leningrad Variation, Warsaw Variation | |
| Nov 25, 2024 | Leht | ½–½ | Bundan | Round 10: Leht, Karl Samuel - Bundan, Edward | Sicilian Defense: Lasker-Pelikan Variation, Sveshnikov Variation, Chelyabinsk Variation | |
| Nov 24, 2024 | Fadeev | ½–½ | Leht | Round 9: Fadeev, Justin Michael - Leht, Karl Samuel | Sicilian Defense: Kan Variation, Polugaevsky Variation | |
| Nov 23, 2024 | Leht | 1–0 | Kim | Round 8: Leht, Karl Samuel - Kim, Minwoo | Italian Game: Evans Gambit, McDonnell Defense | |
| Nov 22, 2024 | Nicot | 1–0 | Leht | Round 7: Nicot, Valentin - Leht, Karl Samuel | Scotch Game: Classical Variation, Intermezzo Variation | |
| Nov 20, 2024 | Leht | 0–1 | Belyaletdinov | Round 6: Leht, Karl Samuel - Belyaletdinov, Leonard | Queen's Gambit Declined: Harrwitz Attack, Fianchetto Defense | |
| Nov 19, 2024 | Chen | ½–½ | Leht | Round 5: Chen, Jun-Wei - Leht, Karl Samuel | Caro-Kann Defense: Tartakower Variation | |
| Nov 18, 2024 | Leht | 1–0 | Williams | Round 4: Leht, Karl Samuel - Williams, Henry | Italian Game: Classical Variation | |
| Nov 17, 2024 | Radnaev | 1–0 | Leht | Round 3: Radnaev, Leo - Leht, Karl Samuel | Italian Game: Classical Variation, Giuoco Pianissimo, with d6 | |
| Nov 16, 2024 | Leht | ½–½ | Skytte | Round 2: Leht, Karl Samuel - Skytte, Robert | Queen's Gambit Declined: Traditional Variation | |
| Nov 15, 2024 | Fulgentini | ½–½ | Leht | Round 1: Fulgentini, Edoardo - Leht, Karl Samuel | Caro-Kann Defense: Tartakower Variation | |
| Jun 11, 2023 | Zabelin | * | Leht | U10 | FIDE World Blitz Championship | ? | |
| Jun 11, 2023 | Deepak Ambattu | 1–0 | Leht | U10 | FIDE World Blitz Championship | Ruy Lopez: Open | |
| Jun 11, 2023 | Zabelin | 1–0 | Leht | U10 | FIDE World Blitz Championship | Queen's Gambit Declined: Exchange Variation, Positional Variation | |
| Jun 10, 2023 | Leht | 1–0 | Rahbar | boys-10 | Sicilian Defense: Hyperaccelerated Fianchetto | |
| Jun 10, 2023 | Leht | 0–1 | Sason | boys-10 | Sicilian Defense: O'Kelly Variation, Normal System | |
| — | Leht | 0–1 | Develi | Round 1: Leht, Karl Samuel - Develi, Kemal Cagan | French Defense: Classical Variation, Shirov-Anand Variation | |
| — | Leht | 0–1 | Beniosev | Round 2: Leht, Karl Samuel - Beniosev, Daniel | Sicilian Defense: Taimanov Variation | |
| — | Beniosev | 0–1 | Leht | Round 1: Beniosev, Daniel - Leht, Karl Samuel | Caro-Kann Defense: Exchange Variation | |