| Jul 2, 2026 | Srinivasson | ½–½ | Ostafiev | Round 6: Srinivasson, Ram - Ostafiev, Cristina | Four Knights Game: Scotch Variation, Belgrade Gambit | |
| Jul 1, 2026 | Ostafiev | 1–0 | Johansson | Round 10: Ostafiev, Cristina - Johansson, Per 1967 | Bird Opening: From's Gambit | |
| Jul 1, 2026 | Kjellgren | * | Ostafiev | Round 11: Kjellgren, Henrik - Ostafiev, Cristina | ? | |
| Jul 1, 2026 | Kring | 1–0 | Ostafiev | Round 9: Kring, Stephan - Ostafiev, Cristina | King's Indian Defense: Orthodox Variation | |
| Jul 1, 2026 | Ostafiev | 1–0 | Hamilton | Round 8: Ostafiev, Cristina - Hamilton, Olov | Bird Opening: Dutch Variation | |
| Jul 1, 2026 | Malm Lindberg | 1–0 | Ostafiev | Round 7: Malm Lindberg, Henrik - Ostafiev, Cristina | Four Knights Game: Scotch Variation Accepted | |
| Jul 1, 2026 | Ostafiev | 1–0 | Cedervall | Round 6: Ostafiev, Cristina - Cedervall, Magnus | Italian Game: Two Knights Defense, Modern Bishop's Opening | |
| Jul 1, 2026 | Klasson | 0–1 | Ostafiev | Round 5: Klasson, Hakan 1961 - Ostafiev, Cristina | Caro-Kann Defense: Accelerated Panov Attack | |
| Jul 1, 2026 | Puleshi | 1–0 | Ostafiev | Round 3: Puleshi, Denis - Ostafiev, Cristina | Semi-Slav Defense | |
| Jul 1, 2026 | Bergdahl | 1–0 | Ostafiev | Round 1: Bergdahl, Martin - Ostafiev, Cristina | Ruy Lopez: Closed, Martinez Variation | |
| Jul 1, 2026 | Ostafiev | ½–½ | Gidlund | Round 5: Ostafiev, Cristina - Gidlund, Viggo | King's Indian Attack: Sicilian Variation | |
| Jun 24, 2026 | Israelsson | 1–0 | Ostafiev | Round 2: Israelsson, Lukas - Ostafiev, Cristina | King's Indian Defense: Kazakh Variation | |
| Apr 26, 2026 | Gultekin | 1–0 | Ostafiev | Nordic girls chess championship 2026 | Italian Game: Giuoco Pianissimo, Italian Four Knights Variation | |
| Apr 26, 2026 | Ostafiev | 1–0 | Sathish | Nordic girls chess championship 2026 | French Defense: King's Indian Attack | |
| Apr 25, 2026 | B. Berglindardottir | * | Ostafiev | Nordic girls chess championship 2026 | King's Indian Defense: Sämisch Variation | |
| Apr 25, 2026 | Ostafiev | 0–1 | Skramstad | Nordic girls chess championship 2026 | Sicilian Defense: Kalashnikov Variation | |
| Apr 24, 2026 | Sigrún Tara Sigurðardóttir | 0–1 | Ostafiev | Nordic girls chess championship 2026 | London System, with Be2 | |
| Oct 11, 2025 | Ostafiev | 0–1 | Krithi Muppirisett | Skol-SM 2025 Kalmar | Sicilian Defense: Dragon Variation, Classical Variation | |
| Apr 27, 2025 | Ostafiev | ½–½ | Ulmer | NM Piger Gruppe B | Caro-Kann Defense: Tartakower Variation | |
| Apr 27, 2025 | Donovan | ½–½ | Ostafiev | NM Piger Gruppe B | Bishop's Opening | |
| Apr 26, 2025 | Ostafiev | 0–1 | Schmalholz | NM Piger Gruppe B | French Defense: Advance Variation | |
| Apr 26, 2025 | Kilina | 0–1 | Ostafiev | NM Piger Gruppe B | Italian Game: Giuoco Piano | |
| Apr 25, 2025 | Ostafiev | 0–1 | Skramstad | NM Piger Gruppe B | Caro-Kann Defense: Main Line | |
| Sep 4, 2022 | Ostafiev | 1–0 | Lindberg | Dam-SM i snabbschack 2022 | French Defense: Advance Variation, Wade Variation | |
| Sep 4, 2022 | Ostafiev | 0–1 | Mariano-Wagman | Dam-SM i snabbschack 2022 | French Defense: Normal Variation | |
| Sep 4, 2022 | Cramling | 1–0 | Ostafiev | Dam-SM i snabbschack 2022 | Slav Defense: Modern Line | |
| Sep 4, 2022 | Olsson | ½–½ | Ostafiev | Dam-SM i snabbschack 2022 | Slav Defense: Exchange Variation | |
| Sep 3, 2022 | Johansson | 1–0 | Ostafiev | Dam-SM i snabbschack 2022 | Slav Defense: Modern Line | |
| Sep 3, 2022 | Berg Laachiri | 1–0 | Ostafiev | Dam-SM i snabbschack 2022 | Scotch Game: Potter Variation | |
| Aug 16, 2021 | Ostafiev | 1–0 | Cassidy Maina | World Youth Cup 2021 O18-G10 - Girls 10 | Sicilian Defense: Closed | |
| Aug 16, 2021 | Ostafiev | 1–0 | Mollo Figueroa | World Youth Cup 2021 O18-G10 - Girls 10 | Sicilian Defense: Closed, Traditional | |
| Aug 16, 2021 | Ostafiev | 0–1 | Krushna Game | World Youth Cup 2021 O18-G10 - Girls 10 | Sicilian Defense: Closed, Traditional | |
| Aug 16, 2021 | Ostafiev | 1–0 | Dalal | World Youth Cup 2021 O18-G10 - Girls 10 | French Defense: Exchange Variation | |
| Aug 16, 2021 | Ostafiev | 0–1 | Diaskyzy | World Youth Cup 2021 O18-G10 - Girls 10 | Sicilian Defense: Closed | |
| Aug 16, 2021 | B | 1–0 | Ostafiev | World Youth Cup 2021 O18-G10 - Girls 10 | Italian Game: Evans Gambit, McDonnell Defense | |
| Aug 16, 2021 | Anemogianni | 0–1 | Ostafiev | World Youth Cup 2021 O18-G10 - Girls 10 | Scotch Game: Lolli Variation | |
| Aug 16, 2021 | Le | 1–0 | Ostafiev | World Youth Cup 2021 O18-G10 - Girls 10 | Italian Game: Classical Variation | |
| Aug 16, 2021 | Beminiwatte | 1–0 | Ostafiev | World Youth Cup 2021 O18-G10 - Girls 10 | Italian Game: Classical Variation | |
| Aug 16, 2021 | Gomez Gonzales | 1–0 | Ostafiev | World Youth Cup 2021 O18-G10 - Girls 10 | Italian Game: Anti-Fried Liver Defense | |