| Game |
| Result | Moves |
Year |
Event/Locale | Opening |
| 1. M Olszewski vs Pavel Rakus |
| 1-0 | 32 |
2005 |
BELFORT YWCC Boys Under 16 | B22 Sicilian, Alapin |
| 2. M Olszewski vs I Brener |
| 1-0 | 30 |
2005 |
BELFORT YWCC Boys Under 16 | B33 Sicilian |
| 3. M Olszewski vs B Thorfinnsson |
| 0-1 | 60 |
2005 |
6th European Individual Championship | B90 Sicilian, Najdorf |
| 4. M Olszewski vs Ma Flores |
| 1-0 | 34 |
2005 |
BELFORT YWCC Boys Under 16 | B22 Sicilian, Alapin |
| 5. M Olszewski vs D Reinderman |
| ½-½ | 58 |
2005 |
6th European Individual Championship | B22 Sicilian, Alapin |
| 6. M Olszewski vs J Vila-Gazquez |
| 1-0 | 14 |
2005 |
BELFORT YWCC Boys Under 16 | B47 Sicilian, Taimanov (Bastrikov) Variation |
| 7. M Olszewski vs M Palac |
| 0-1 | 32 |
2005 |
6th European Individual Championship | B90 Sicilian, Najdorf |
| 8. M Olszewski vs M Lapcevic |
| ½-½ | 64 |
2006 |
European Youth Championship | B22 Sicilian, Alapin |
| 9. M Olszewski vs Savchenko |
| 0-1 | 22 |
2008 |
XXIV Open | B20 Sicilian |
| 10. M Olszewski vs R Kempinski |
| ½-½ | 90 |
2008 |
Najdorf Memorial | B91 Sicilian, Najdorf, Zagreb (Fianchetto) Variation |
| 11. M Olszewski vs R Wojtaszek |
| ½-½ | 14 |
2009 |
Najdorf Memorial | B80 Sicilian, Scheveningen |
