Callahan, John M
Current rating: 1572
Record: 9-6
| Grand Prix Atlantic City 2015 (DTK limited) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 217 | Candee, Timothy (1500) | Won 2-0 | +181518 |
| 2sealed | 308 | Spartz, Emerson (1568) | Won 2-0 | +191537 |
| 3sealed | 78 | Siembor, Michael (1456) | Lost 1-2 | -201517 |
| 4sealed | 457 | Rutkowski, Alexander (1510) | Won 2-1 | +181535 |
| 5sealed | 346 | McKelvey, Daniel (1557) | Lost 0-2 | -171518 |
| 6sealed | 348 | Watson, Brendan (1485) | Won 2-0 | +171535 |
| 7sealed | 317 | Hwang, Eugene (1985) | Won 2-0 | +261561 |
| 8sealed | 156 | Kandziolka, James (1653) | Won 2-0 | +191580 |
| 9sealed | 75 | Tse, Jay (1750) | Won 2-0 | +221602 |
| 10draft | 77 | Tenjum, Andrew (1911) | Lost 0-2 | -131589 |
| 11draft | 35 | McKelvey, Daniel (1603) | Won 2-0 | +181607 |
| 12draft | 41 | Alvarez, Lance (1683) | Lost 1-2 | -161591 |
| 13draft | 19 | Munger, Kevin (1538) | Won 2-0 | +171608 |
| 14draft | 72 | Calderon, Christopher (1644) | Lost 0-2 | -181590 |
| 15draft | 67 | Sandine, Ely (1553) | Lost 0-2 | -181572 |
| average opponent: 1626record: 9-6 | new rating: 1572 | |||