Zadrejko, Jonathan
Current rating: 1553
| Grand Prix Philadelphia 2012 (RTR limited) | starting rating: 1531 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 117 | Mann, Corey (1506) | Lost 1-2 | -181513 |
| 2sealed | 318 | Nowakowski, Stephen (1540) | Won 2-0 | +181531 |
| 3sealed | 241 | Bauer, David (1674) | Won 2-0 | +211552 |
| 4sealed | 166 | Price, Pat (1694) | Lost 1-2 | -151537 |
| 5sealed | 340 | Kingsbury, Lyle (1456) | Won 2-0 | +161553 |
| top | average opponent: 1574record: 3-2 | new rating: 1553 | ||
| Grand Prix Philadelphia 2008 (extended) | starting rating: 1463 | |||
| round | table | opponent (rating) | result | Δrating |
| 1extended | 245 | Francis, Christopher W (1463) | Won 2-1 | +181481 |
| 2extended | 150 | Pettengill, Morgan (1517) | Won 2-1 | +191500 |
| 3extended | 63 | Hinkle, Charles (1482) | Won 2-1 | +181518 |
| 4extended | 80 | Imperiale, Jason (1837) | Draw 1-1 | +51523 |
| 5extended | 58 | Visconti, Michael (1614) | Won 2-1 | +201543 |
| 6extended | 31 | Edel, Willy (1778) | Lost 0-2 | -141529 |
| 7extended | 81 | Kozlowski, Kevin S (1557) | Won 2-0 | +191548 |
| 8extended | 46 | Sukenik, Jonathan (1535) | Won 2-0 | +171565 |
| 9extended | 29 | O'Donnell, Brendan (1659) | Lost 0-2 | -161549 |
| 10extended | 56 | Narchus, Nick J (1564) | Lost 0-2 | -181531 |
| top | average opponent: 1601record: 6-3-1 | new rating: 1531 | ||
| Grand Prix Philadelphia 2002 (ONS rochester) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 64 | LaClaire, Larry (1480) | Lost 0-2 | -181482 |
| 2sealed | 212 | Flurie, Alex (1482) | Won 2-0 | +181500 |
| 3sealed | 204 | Oakley, Matthew (1500) | Lost 0-2 | -181482 |
| 4sealed | 194 | Stefanovic, Lou (1464) | Lost 0-2 | -191463 |
| top | average opponent: 1482record: 1-3 | new rating: 1463 | ||