Kumagai, Hidekazu
Current rating: 1500
Record: 3-3
| Grand Prix Yokohama 2004 (COK limited) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 27 | Itou, Takanori (1460) | Won 2-1 | +171517 |
| 2sealed | 15 | Yamano, Tatsuto (1439) | Won 2-0 | +171534 |
| 3sealed | 15 | Ito, Atsushi (1547) | Won 2-0 | +181552 |
| 4sealed | 32 | Saito, Takaya (1590) | Lost 0-2 | -171535 |
| 5sealed | 89 | Tanaka, Ryota (1520) | Lost 0-2 | -181517 |
| 6sealed | 160 | Murayama, Yoshiyuki (1619) | Lost 1-2 | -171500 |
| average opponent: 1529record: 3-3 | new rating: 1500 | |||