Ishiduka, Hazime
Current rating: 1444
Record: 11-15-1
| Grand Prix Yokohama 2013 (GTC limited) | starting rating: 1498 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 49 | Iseki, Takao (1500) | Lost 0-2 | -181480 |
| 2sealed | 426 | Kawamata, Takuya (1485) | Lost 0-2 | -181462 |
| 3sealed | 498 | Nishio, Yoshihiro (1441) | Lost 0-2 | -181444 |
| top | average opponent: 1475record: 0-3 | new rating: 1444 | ||
| Grand Prix Yokohama 2004 (COK limited) | starting rating: 1486 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 105 | Sugiura, Hiroki (1539) | Won 2-1 | +191505 |
| 2sealed | 76 | Matsuyama, Satoshi (1504) | Won 2-0 | +181523 |
| 3sealed | 31 | Okada, Kou (1706) | Lost 0-2 | -151508 |
| 4sealed | 125 | Maruyama, Tomohiro (1645) | Won 2-1 | +211529 |
| 5sealed | 111 | Kishigami, Osamu (1518) | Won 2-0 | +181547 |
| 6sealed | 83 | Suzuki, Masatsuna (1719) | Lost 0-2 | -151532 |
| 7sealed | 61 | Fuma, Masaharu (1645) | Lost 1-2 | -161516 |
| 8sealed | 93 | Oikawa, Mutsuki (1513) | Lost 1-2 | -181498 |
| top | average opponent: 1599record: 4-4 | new rating: 1498 | ||
| Grand Prix Sendai 2004 (DST limited) | starting rating: 1465 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 12 | Nozaki, Yoshinori (1464) | Won 2-0 | +181483 |
| 2sealed | 76 | Furuya, Masashi (1580) | Won 2-1 | +201503 |
| 3sealed | 61 | Kitamura, Hiroaki (1536) | Lost 1-2 | -171486 |
| 4sealed | 64 | Kobayashi, Hiroki (1517) | Lost 0-2 | -181468 |
| 5sealed | 132 | Matsuyama, Satoshi (1465) | Draw 1-1 | 01468 |
| 6sealed | 140 | Nakazato, Takuya (1451) | Won 2-1 | +181486 |
| 7sealed | 101 | Hattori, Keitarou (1465) | Lost 1-2 | -181468 |
| 8sealed | 99 | Fukui, Yohei (1496) | Won 2-0 | +181486 |
| top | average opponent: 1497record: 4-3-1 | new rating: 1486 | ||
| Grand Prix Yokohama 2003 (Onslaught block) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1block | 178 | Ishigami, Kazuya (1500) | Lost 1-2 | -181482 |
| 2block | 257 | Tatsumi, Yasuhiro (1482) | Lost 0-2 | -181464 |
| 3block | 371 | Aizawa, Keiji (1464) | Lost 1-2 | -181446 |
| 4block | 375 | Konno, Daisuke (1445) | Won 2-0 | +181464 |
| 5block | 342 | Fujimoto, Keiji (1462) | Won 2-0 | +181482 |
| 6block | 274 | Fukuchi, Takahiro (1578) | Lost 0-2 | -161466 |
| 7block | 271 | Okada, Hiroaki(Shiga) (1445) | Lost 0-2 | -191447 |
| 8block | 248 | Saito, Shuichi (1456) | Won 2-0 | +181465 |
| top | average opponent: 1479record: 3-5 | new rating: 1465 | ||