Marek Jr., David
Current rating: 1477
| Grand Prix Charlotte 2016 (modern) | starting rating: 1474 | |||
| round | table | opponent (rating) | result | Δrating |
| 1modern | 81 | Miklancic, Ethan (1500) | Won 2-1 | +191493 |
| 2modern | 324 | Mains, Matthew (1462) | Won 2-1 | +171510 |
| 3modern | 473 | Smith, Christina (1467) | Lost 1-2 | -191491 |
| 4modern | 659 | Schaffluetzel, Lester (1523) | Lost 1-2 | -171474 |
| 5modern | 558 | Henry, Erik (1500) | Won 2-1 | +181492 |
| 6modern | 353 | Miller, Myles (1505) | Won 2-1 | +191511 |
| 7modern | 399 | Moore, CJ (1609) | Lost 0-2 | -171494 |
| 8modern | 513 | Nickle, Derrick (1551) | Lost 0-2 | -171477 |
| top | average opponent: 1515record: 4-4 | new rating: 1477 | ||
| Grand Prix Pittsburgh 2015 (modern) | starting rating: 1512 | |||
| round | table | opponent (rating) | result | Δrating |
| 1modern | 512 | Beaudoin, Lance (1500) | Lost 1-2 | -191493 |
| 2modern | 685 | Larson, Mark (1570) | Lost 0-2 | -161477 |
| 3modern | 1157 | Swanson, Aaron (1463) | Won 2-0 | +181495 |
| 4modern | 944 | Turnbull, Chris (1390) | Lost 0-2 | -201475 |
| 5modern | 1099 | Hall, Christopher (1469) | Won 2-0 | +181493 |
| 6modern | 876 | Grossfeld, Nathan (1470) | Lost 1-2 | -191474 |
| top | average opponent: 1477record: 2-4 | new rating: 1474 | ||
| Grand Prix Charlotte 2015 (modern) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1modern | 1393 | Shatz, Andrew (1447) | Won 2-1 | +171517 |
| 2modern | 1361 | Freeman, Chris N (1482) | Won 2-0 | +171534 |
| 3modern | 1383 | Greenidge, Jamal (1421) | Won 2-1 | +161550 |
| 4modern | 1260 | Hutton, Daniel (1596) | Lost 0-2 | -171533 |
| 5modern | 1206 | Silvers, Cody (1467) | Lost 1-2 | -191514 |
| 6modern | 1244 | Bowles, Ed (1457) | Won 2-1 | +171531 |
| 7modern | 1132 | Martin, Steven L (1458) | Lost 0-2 | -191512 |
| top | average opponent: 1476record: 4-3 | new rating: 1512 | ||