| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 26. Franz Zoister vs O Koeller |
| 0-1 | 34 | 1999 | Danube Open | B77 Sicilian, Dragon, Yugoslav Attack |
| 27. O Koeller vs G Kreischer |
| 1-0 | 26 | 1999 | Danube Open | C10 French |
| 28. M Stein vs O Koeller |
| 0-1 | 53 | 2000 | Bad Zwesten Open | E70 King's Indian |
| 29. O Koeller vs M Schmitt |
| ½-½ | 8 | 2000 | Bad Zwesten Open | B07 Pirc |
| 30. S Bravo Lutz vs O Koeller |
| ½-½ | 11 | 2000 | Bad Zwesten Open | B76 Sicilian, Dragon, Yugoslav Attack |
| 31. M Rack vs O Koeller |
| 0-1 | 24 | 2000 | Bad Zwesten Open | E70 King's Indian |
| 32. O Koeller vs R Koops |
| 1-0 | 19 | 2000 | Bad Zwesten Open | B00 Uncommon King's Pawn Opening |
| 33. G Richter vs O Koeller |
| ½-½ | 21 | 2000 | Bad Zwesten Open | B72 Sicilian, Dragon |
| 34. O Koeller vs J Marth |
| ½-½ | 42 | 2000 | Bad Zwesten Open | C00 French Defense |
| 35. O Koeller vs D Ciornei |
| ½-½ | 27 | 2000 | Bad Zwesten Open | C45 Scotch Game |
| 36. O Koeller vs Naiditsch |
| ½-½ | 38 | 2000 | Bad Zwesten Open | B50 Sicilian |
| 37. S Reschke vs O Koeller |
| 1-0 | 13 | 2000 | Oberliga Ost-B 9900 | E62 King's Indian, Fianchetto |
| 38. J Knickel vs O Koeller |
| 0-1 | 43 | 2002 | Bad Zwesten Open | B30 Sicilian |
| 39. Naiditsch vs O Koeller |
| 1-0 | 35 | 2002 | Bad Zwesten Open | B32 Sicilian |
| 40. O Koeller vs I Ruetten |
| 1-0 | 23 | 2002 | Bad Zwesten Open | B51 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 41. O Koeller vs M Stein |
| 0-1 | 27 | 2002 | Bad Zwesten Open | B77 Sicilian, Dragon, Yugoslav Attack |
| 42. O Koeller vs F Bindrich |
| 1-0 | 32 | 2002 | Bad Zwesten Open | B52 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 43. B Lauer vs O Koeller |
| 0-1 | 55 | 2002 | Bad Zwesten Open | A22 English |
| 44. J Marth vs O Koeller |
| 1-0 | 60 | 2002 | Bad Zwesten Open | B30 Sicilian |
| 45. O Koeller vs W Langer |
| ½-½ | 10 | 2002 | Bad Zwesten Open | B51 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 46. B Ruecker vs O Koeller |
| 1-0 | 35 | 2002 | Bad Zwesten Open | B78 Sicilian, Dragon, Yugoslav Attack, 10.castle long |
| 47. P Wang vs O Koeller |
| 0-1 | 50 | 2004 | Auckland Open | B06 Robatsch |
Kibitzing
