Koyama, Takahiro
Current rating: 1446
Record: 13-19-1
| Grand Prix Kyoto 2015 (legacy) | starting rating: 1501 | |||
| round | table | opponent (rating) | result | Δrating |
| 1legacy | 579 | Sasahara, Yasutaka (1498) | Lost 0-2 | -181483 |
| 2legacy | 842 | Uehira, Shinichi (1442) | Lost 0-2 | -191464 |
| 3legacy | 958 | Tanabe, Koichiro (1430) | Lost 1-2 | -181446 |
| 4legacy | 967 | Funahara, Kazuya (1338) | Won 2-1 | +161462 |
| 5legacy | 919 | Shigehisa, Tetsuya (1571) | Won 2-1 | +201482 |
| 6legacy | 827 | Sakai, Yoshiki (1511) | Lost 1-2 | -181464 |
| 7legacy | 811 | Morishige, Yosuke (1460) | Lost 1-2 | -181446 |
| top | average opponent: 1464record: 2-5 | new rating: 1446 | ||
| Grand Prix Sendai 2010 (ROE standard) | starting rating: 1466 | |||
| round | table | opponent (rating) | result | Δrating |
| 1standard | 316 | Leary, Michael (1500) | Won 2-0 | +181484 |
| 2standard | 70 | Shingai, Sara (1718) | Won 2-1 | +221506 |
| 3standard | 85 | Honnami, Tomoyuki (1737) | Won 2-1 | +231529 |
| 4standard | 72 | Shirotori, Ryousuke (1555) | Lost 0-2 | -181511 |
| 5standard | 72 | Watanabe, Takanori (1638) | Won 2-0 | +201531 |
| 6standard | 75 | Akimoto, Shinichi (1537) | Won 2-1 | +181549 |
| 7standard | 56 | Ueki, Yoshinori (1571) | Lost 0-2 | -171532 |
| 8standard | 56 | Shiraishi, Tomomi (1858) | Lost 1-2 | -121520 |
| 9standard | 110 | Sekizawa, Takayuki (1503) | Lost 1-2 | -191501 |
| top | average opponent: 1624record: 5-4 | new rating: 1501 | ||
| Grand Prix Shizuoka 2008 (MOR standard) | starting rating: 1498 | |||
| round | table | opponent (rating) | result | Δrating |
| 1standard | 165 | Hassaku, Jinpei (1703) | Lost 1-2 | -141484 |
| 2standard | 327 | fukuda, bunpei (1483) | Lost 1-2 | -181466 |
| 3standard | 369 | Suzuki, Mikito (1485) | Won 2-0 | +181484 |
| 4standard | 357 | Kurisu, Takashi (1440) | Draw 1-1 | 01484 |
| 5standard | 297 | Okuzaki, Satoru (1482) | Lost 1-2 | -181466 |
| top | average opponent: 1518record: 1-3-1 | new rating: 1466 | ||
| Grand Prix Kyoto 2007 (PLC standard) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 4standard | 88 | Fujita, Tsuyoshi (1807) | Won 2-1 | +231523 |
| 5standard | 1 | Imai, Hideaki (1486) | Won 2-0 | +181541 |
| 6standard | 15 | Minami, Masashi (1739) | Lost 1-2 | -151526 |
| 7standard | 37 | Furuya, Yuuki (1578) | Won 2-1 | +191545 |
| 8standard | 28 | Ito, Atsushi (1475) | Won 2-0 | +171562 |
| 9standard | 11 | Morita, Masahiko (2004) | Lost 0-2 | -101552 |
| 10standard | 57 | Kurihara, Shingou (2070) | Lost 0-2 | -101542 |
| 11standard | 11 | Taru, Genki (1750) | Lost 0-2 | -141528 |
| 12standard | 49 | Shigehara, Toshinori (1644) | Lost 0-2 | -161512 |
| 13standard | 29 | Tamada, Ryoichi (1642) | Lost 0-2 | -161496 |
| 14standard | 48 | Chao, Peter (1564) | Lost 1-2 | -161480 |
| 15standard | 55 | Miwa, Tatsuya (1525) | Won 2-1 | +181498 |
| top | average opponent: 1690record: 5-7 | new rating: 1498 | ||