Mattila, Juhani
Current rating: 1428
Record: 1-5
| Grand Prix Helsinki 2004 (COK limited) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 130 | Lehtinen, Max (1501) | Lost 0-2 | -181482 |
| 2sealed | 177 | Stavas, Ola (1436) | Lost 1-2 | -191463 |
| 3sealed | 169 | Elomaa, Veijo (1463) | Lost 0-2 | -181445 |
| 4sealed | 207 | Kukkola, Jonne (1448) | Won 2-1 | +181463 |
| 5sealed | 182 | Lia, Fredrik (1482) | Lost 0-2 | -171446 |
| 6sealed | 162 | Hietalahti, Matti (1449) | Lost 0-2 | -181428 |
| average opponent: 1463record: 1-5 | new rating: 1428 | |||