| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 26. A Kuru vs S Otsuka |
| 1-0 | 37 | 2025 | 23rd Marienbad A1 GM | C45 Scotch Game |
| 27. V V Shah vs S Otsuka |
| 1-0 | 49 | 2025 | Pilsen GM | C78 Ruy Lopez |
| 28. S Otsuka vs M Petr |
| 0-1 | 67 | 2025 | Pilsen GM | B40 Sicilian |
| 29. T Kuegel vs S Otsuka |
| 1-0 | 41 | 2025 | Pilsen GM | C55 Two Knights Defense |
| 30. P Neuman vs S Otsuka |
| 0-1 | 41 | 2025 | Pilsen GM | D35 Queen's Gambit Declined |
| 31. S Otsuka vs M Mattenberger |
 | 1-0 | 42 | 2025 | Pilsen GM | B51 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 32. Y Song vs S Otsuka |
| ½-½ | 60 | 2025 | Pilsen GM | C45 Scotch Game |
| 33. S Otsuka vs M Pacher |
| ½-½ | 24 | 2025 | Pilsen GM | C42 Petrov Defense |
| 34. Y Zhao vs S Otsuka |
| 1-0 | 57 | 2025 | Pilsen GM | A45 Queen's Pawn Game |
| 35. S Otsuka vs C Krishna |
| 0-1 | 46 | 2025 | Pilsen GM | C01 French, Exchange |
| 36. D Makhnev vs S Otsuka |
| ½-½ | 23 | 2025 | Asian Championship | D38 Queen's Gambit Declined, Ragozin Variation |
| 37. S Otsuka vs Sharma Ayush |
| ½-½ | 23 | 2025 | Asian Championship | B52 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 38. S Gan-Erdene vs S Otsuka |
| 1-0 | 53 | 2025 | Asian Championship | C11 French |
| 39. S Otsuka vs S Vetokhin |
| 0-1 | 38 | 2025 | Asian Championship | B51 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 40. Y Fu vs S Otsuka |
| 0-1 | 61 | 2025 | Asian Championship | C02 French, Advance |
| 41. S Otsuka vs T Pang |
| ½-½ | 27 | 2025 | Asian Championship | C01 French, Exchange |
| 42. D Quizon vs S Otsuka |
| ½-½ | 47 | 2025 | Asian Championship | C77 Ruy Lopez |
| 43. S Otsuka vs N Priasmoro |
| 1-0 | 70 | 2025 | Asian Championship | B06 Robatsch |
| 44. I Rozum vs S Otsuka |
| 0-1 | 40 | 2025 | Asian Championship | D32 Queen's Gambit Declined, Tarrasch |
| 45. S Otsuka vs A Hoffmann |
| 1-0 | 30 | 2025 | Biel Master Open | B52 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 46. A Tureshbayev vs S Otsuka |
| ½-½ | 104 | 2025 | Biel Master Open | B32 Sicilian |
| 47. S Otsuka vs Yash Abhijit Patil |
| 1-0 | 24 | 2025 | Biel Master Open | C05 French, Tarrasch |
| 48. S Otsuka vs M Pranesh |
| ½-½ | 65 | 2025 | Biel Master Open | C55 Two Knights Defense |
| 49. K J Soo vs S Otsuka |
| 1-0 | 31 | 2025 | Biel Master Open | A62 Benoni, Fianchetto Variation |
| 50. A Shvedova vs S Otsuka |
| ½-½ | 60 | 2025 | Biel Master Open | C11 French |
Kibitzing
