Mark Klaassen
Last tournaments played
| Tournament | Date | Elo Avg. | Country |
| NED-ch U12 op | 08/07/2000 | 0 |  Netherlands |
| NED U12 op | ??/??/1999 | 0 | Netherlands |
| Hengelo U12 op | ??/??/1998 | 0 | Netherlands |
| Hengelo op U12 | ??/??/1997 | 0 | Netherlands |
Most Played Openings as White
| ECO | Opening | Games |
| C02 | French, advance variation | 1 games |
| C48 | Four knights, Spanish variation | 1 games |
| B80 | Sicilian, Scheveningen variation | 1 games |
Most Played Openings as Black
| ECO | Opening | Games |
| C50 | King's pawn game | 2 games |
| C45 | Scotch game | 1 games |
| A34 | English, symmetrical variation | 1 games |
| C62 | Ruy Lopez, old Steinitz defence | 1 games |
