Portwood, John
Current rating: 1503
Record: 3-3
| Grand Prix Dallas-Fort Worth 2015 (ORI limited) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 144 | Andrup, Alex (1705) | Lost 1-2 | -141486 |
| 2sealed | 389 | Mitchell, Isaak (1481) | Won 2-0 | +181504 |
| 3sealed | 350 | Bloch, Trevor (1499) | Won 2-0 | +181522 |
| 4sealed | 317 | Templer, Nick (1518) | Won 2-1 | +171539 |
| 5sealed | 156 | Preston, Jeff (1504) | Lost 0-2 | -181521 |
| 6sealed | 246 | Zylks, Jeffrey (1523) | Lost 0-2 | -181503 |
| average opponent: 1538record: 3-3 | new rating: 1503 | |||