Shaffner, Zack S
Current rating: 1533
| Grand Prix Charlotte 2013 (GTC limited) | starting rating: 1555 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 960 | Redman, Kelly (1500) | Lost 1-2 | -191536 |
| 2sealed | 1114 | Dvorzsak, Devon (1482) | Won 2-1 | +171553 |
| 3sealed | 904 | Eden, Kyle (1431) | Lost 1-2 | -201533 |
| top | average opponent: 1471record: 1-2 | new rating: 1533 | ||
| Grand Prix Atlanta 2011 (extended) | starting rating: 1519 | |||
| round | table | opponent (rating) | result | Δrating |
| 1extended | 540 | Basseri, Yashar (1504) | Won 2-0 | +181537 |
| 2extended | 405 | Johanson, Tyler (1518) | Won 2-1 | +181555 |
| 3extended | 413 | Benson, Jonathan (1656) | Lost 1-2 | -161539 |
| 4extended | 549 | Walsh, Jake M (1520) | Lost 0-2 | -191520 |
| 5extended | 570 | Peretz, Michael (1455) | Won 2-0 | +171537 |
| 6extended | 548 | Gaines, Scott G (1518) | Won 2-0 | +181555 |
| 7extended | 465 | Ohlschwager, Andrew (1570) | Won 2-0 | +181573 |
| 8extended | 446 | McGill, Clint (1585) | Lost 1-2 | -181555 |
| top | average opponent: 1541record: 5-3 | new rating: 1555 | ||
| Grand Prix Nashville 2010 (SOM limited) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 197 | Rogers, Trevor J (1500) | Won 2-1 | +181518 |
| 2sealed | 125 | Meyer, Chad (1523) | Lost 0-2 | -181500 |
| 3sealed | 219 | Flieg, Jeff (1493) | Won 2-1 | +181518 |
| 4sealed | 118 | Sussino, Tim (1623) | Lost 0-2 | -161502 |
| 5sealed | 240 | Beebe, Berry (1487) | Won 2-1 | +181520 |
| 6sealed | 174 | Perdue, Heath (1518) | Won 2-1 | +181538 |
| 7sealed | 96 | Dunbar, Heath (1531) | Lost 1-2 | -191519 |
| top | average opponent: 1525record: 4-3 | new rating: 1519 | ||