Jeon, Yong Sun
Current rating: 1460
Record: 3-5
| Grand Prix Matsuyama 2005 (BOK limited) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 46 | Honda, Yuuki (1500) | Lost 0-2 | -181482 |
| 2sealed | 112 | Hayashi, Yuki (1493) | Lost 1-2 | -181464 |
| 3sealed | 160 | Satou, Yoshirou (1463) | Won 2-0 | +181482 |
| 4sealed | 152 | saitou, yutaka (1482) | Won 2-1 | +181500 |
| 5sealed | 114 | Yamashita, Kohji (1430) | Won 2-0 | +171517 |
| 6sealed | 100 | Ito, Hidetoshi (1427) | Lost 1-2 | -201497 |
| 7sealed | 100 | Yamane, Masahiro (1470) | Lost 0-2 | -181479 |
| 8sealed | 98 | Maruyama, Kentarou (1440) | Lost 0-2 | -191460 |
| average opponent: 1463record: 3-5 | new rating: 1460 | |||