Pfefferkorn, Jakob
Current rating: 1445
| Grand Prix Bochum 2010 (SOM limited) | starting rating: 1415 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 134 | Singh, Alexej (1500) | Won 2-1 | +191434 |
| 2sealed | 185 | van Reijmersdal, Niels (1487) | Won 2-0 | +191453 |
| 3sealed | 40 | Lange, Robert (1564) | Won 2-0 | +201473 |
| 4sealed | 10 | Van Malderen, Davy (1520) | Won 2-1 | +191492 |
| 5sealed | 20 | Florea, Dan (1611) | Lost 0-2 | -161476 |
| 6sealed | 53 | Engelberg, Lars Jorgen (1657) | Lost 1-2 | -141462 |
| 7sealed | 169 | Weier, Daniel (1521) | Lost 0-2 | -171445 |
| top | average opponent: 1551record: 4-3 | new rating: 1445 | ||
| Grand Prix Prague 2009 (M10 limited) | starting rating: 1466 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 735 | Mantovani, Davide (1445) | Won 2-0 | +181484 |
| 2sealed | 511 | Pietron, Krzysztof (1532) | Lost 0-2 | -181466 |
| 3sealed | 772 | Starek, Jakub (1570) | Lost 0-2 | -161450 |
| 4sealed | 754 | Vragovic, Predrag (1464) | Lost 1-2 | -171433 |
| 5sealed | 810 | Csaba, Denes (1445) | Lost 0-2 | -181415 |
| top | average opponent: 1491record: 1-4 | new rating: 1415 | ||
| Grand Prix Hanover 2009 (extended) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1extended | 26 | Henze, Oliver (1489) | Lost 0-2 | -181482 |
| 2extended | 140 | Holtmann, Jens (1501) | Won 2-0 | +181500 |
| 3extended | 94 | Serowy, Arno (1500) | Lost 0-2 | -181482 |
| 4extended | 200 | Saporita, Max (1482) | Lost 0-0 | -181464 |
| 5extended | 185 | Kiehn, Manuel (1464) | Lost 1-2 | -181446 |
| 6extended | 184 | Brinkmann, Jan (1542) | Lost 1-2 | -161430 |
| 7extended | 161 | Schov, Michael (1423) | Won 2-0 | +181448 |
| 8extended | 129 | Kruse, Marco (1457) | Won 2-0 | +181466 |
| top | average opponent: 1482record: 3-5 | new rating: 1466 | ||