Piedra Mora, David
Current rating: 1560
Record: 12-9
| Grand Prix Costa Rica 2012 (M13 limited) | starting rating: 1558 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 60 | Acuna, Heilyn (1500) | Won 2-1 | +161574 |
| 3sealed | 43 | Zuniga, Cristian (1721) | Lost 0-2 | -151559 |
| 4sealed | 49 | Salazar, Jesus (1502) | Lost 1-2 | -191540 |
| 5sealed | 93 | Dobles Morales, Robert (1483) | Won 2-1 | +171557 |
| 6sealed | 86 | Gomez, Teodosis Gavriel (1503) | Won 2-1 | +171574 |
| 7sealed | 35 | Ro, Alan (1537) | Won 2-0 | +171591 |
| 8sealed | 44 | Ortiz, Oliver (1536) | Won 2-1 | +171608 |
| 9draft | 8 | Hastedt, Carlos Emilio (1540) | Lost 1-2 | -191589 |
| 10draft | 24 | Alvarado, Saul (1856) | Won 2-1 | +231612 |
| 11draft | 19 | Virula, Christopher (1539) | Lost 0-2 | -191593 |
| 13draft | 9 | Alvarado, Saul (1858) | Lost 0-2 | -141579 |
| 14draft | 16 | Salazar, Jesus (1527) | Lost 0-2 | -191560 |
| average opponent: 1592record: 6-6 | new rating: 1560 | |||
| Grand Prix Boston 2009 (M10 limited) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 595 | Dolan, Eric (1429) | Lost 1-2 | -191481 |
| 2sealed | 651 | Brazzell, Davis (1499) | Won 2-0 | +181499 |
| 3sealed | 667 | Martelli, Paul (1500) | Won 2-0 | +181517 |
| 4sealed | 508 | Kane, DeWitt (1665) | Lost 0-2 | -151502 |
| 5sealed | 574 | Welzbacher, Jordan (1500) | Lost 1-2 | -181484 |
| 6sealed | 620 | Morris, Robert (1502) | Won 2-0 | +181502 |
| 7sealed | 555 | Robinson, Jesse (1504) | Won 2-0 | +181520 |
| 8sealed | 519 | Izzo, Anthony (1588) | Won 2-1 | +191539 |
| 9sealed | 478 | Legler, Tad (1552) | Won 2-0 | +191558 |
| average opponent: 1526record: 6-3 | new rating: 1558 | |||