Marshall, Shawn
Current rating: 1488
Record: 25-31-5
| Grand Prix New Jersey 2020 (THB limited) | starting rating: 1453 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 405 | Wilgus III, Philip (1330) | Won 2-1 | +161469 |
| 2sealed | 295 | Behrens, Joseph (1652) | Lost 1-2 | -151454 |
| 3sealed | 540 | Fazekas, Jeffrey (1628) | Won 2-0 | +211475 |
| 4sealed | 224 | Wong, Matthew (1697) | Won 2-0 | +221497 |
| 5sealed | 271 | Benderly-Kraft, Sasha (1541) | Lost 1-2 | -171480 |
| 6sealed | 320 | Tan, Richard (1895) | Won 2-0 | +251505 |
| 7sealed | 182 | Dias, Manuel (1572) | Lost 1-2 | -171488 |
| top | average opponent: 1617record: 4-3 | new rating: 1488 | ||
| Grand Prix Phoenix 2019 (ELD limited) | starting rating: 1487 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 170 | Mascarenhas, Miguel (1573) | Lost 0-2 | -171470 |
| 2sealed | 181 | Rhey, Martin (1482) | Lost 0-2 | -181452 |
| 3sealed | 233 | Johnson, Jack (1530) | Won 2-0 | +201472 |
| 4sealed | 192 | Allen, Nolan (1422) | Lost 1-2 | -191453 |
| top | average opponent: 1502record: 1-3 | new rating: 1453 | ||
| Grand Prix Toronto 2010 (SOM limited) | starting rating: 1463 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 234 | Pearson, Dennis (1500) | Won 2-0 | +181481 |
| 2sealed | 139 | Taylor, Paul H (1553) | Won 2-0 | +201501 |
| 3sealed | 80 | Morelli, Mike (1535) | Lost 0-2 | -181483 |
| 4sealed | 86 | Walker, Noah (1539) | Won 2-0 | +191502 |
| 5sealed | 48 | Moir, Ben (1619) | Lost 0-2 | -151487 |
| top | average opponent: 1549record: 3-2 | new rating: 1487 | ||
| Grand Prix Boston 2009 (M10 limited) | starting rating: 1454 | |||
| round | table | opponent (rating) | result | Δrating |
| 2sealed | 177 | Kemper, Greg (1524) | Won 2-0 | +191473 |
| 3sealed | 63 | Croes, Ben (1517) | Won 2-0 | +191492 |
| 4sealed | 14 | English, Eric (1536) | Lost 1-2 | -171475 |
| 5sealed | 155 | Felske, David (1702) | Lost 1-2 | -141461 |
| 6sealed | 112 | Fyffe, Colin (1519) | Won 2-0 | +191480 |
| 7sealed | 114 | Gilbert, Nicholas (1539) | Lost 0-2 | -171463 |
| top | average opponent: 1556record: 3-3 | new rating: 1463 | ||
| Grand Prix New Jersey 2006 (TSP limited) | starting rating: 1447 | |||
| round | table | opponent (rating) | result | Δrating |
| 2sealed | 190 | Scott, Todd (1405) | Draw 1-1 | -11446 |
| 3sealed | 162 | Friedman, Murray F (1517) | Lost 0-2 | -161430 |
| 4sealed | 282 | Morgan, Sean (1518) | Draw 1-1 | +11431 |
| 5sealed | 310 | Newman, Travis A (1482) | Won 2-1 | +191450 |
| 6sealed | 245 | Wagner, Andrew C (1510) | Won 2-1 | +191469 |
| 7sealed | 184 | Rosman-Simionescu, Tobias (1598) | Lost 0-2 | -151454 |
| top | average opponent: 1505record: 2-2-2 | new rating: 1454 | ||
| Grand Prix Toronto 2006 (DIS limited) | starting rating: 1418 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 100 | Hryniuk, Graham (1500) | Won 2-0 | +191437 |
| 2sealed | 1 | McLaughlin, Morgan (1558) | Lost 0-2 | -151422 |
| 3sealed | 87 | Fischer, Jeff (1449) | Won 2-1 | +181440 |
| 4sealed | 109 | Kunkel, Jeremy (1447) | Draw 1-1 | 01440 |
| 5sealed | 106 | Papamatheakis, Demosthenes (1459) | Won 1-0 | +191459 |
| 6sealed | 69 | Krempels, Craig (1837) | Lost 0-2 | -121447 |
| top | average opponent: 1542record: 3-2-1 | new rating: 1447 | ||
| Grand Prix Boston 2005 (extended) | starting rating: 1448 | |||
| round | table | opponent (rating) | result | Δrating |
| 1extended | 38 | Jones, Michael (1549) | Lost 0-2 | -161432 |
| 2extended | 269 | Hann, Jackson (1482) | Won 2-0 | +191451 |
| 3extended | 146 | Li, Chester (1500) | Lost 0-2 | -171434 |
| 4extended | 264 | Bongiovanni, Mauro (1568) | Lost 1-2 | -161418 |
| top | average opponent: 1525record: 1-3 | new rating: 1418 | ||
| Grand Prix New Jersey 2004 (Mirrodin block) | starting rating: 1431 | |||
| round | table | opponent (rating) | result | Δrating |
| 2block | 182 | Stokes, Jesse (1518) | Won 2-0 | +191450 |
| 3block | 119 | Cabrera, David (1518) | Won 2-1 | +201470 |
| 4block | 18 | Ruel, Olivier (2018) | Lost 1-2 | -91461 |
| 5block | 95 | Mays, Rich (1491) | Won 2-1 | +181479 |
| 6block | 113 | Labenski, Michael (1536) | Won 2-1 | +191498 |
| 7block | 34 | Vandover, Sean (1585) | Lost 1-2 | -161482 |
| 8block | 86 | Hammond, Matthew (1550) | Lost 0-2 | -171465 |
| 9block | 139 | Badding, Duncan (1509) | Lost 1-2 | -171448 |
| top | average opponent: 1591record: 4-4 | new rating: 1448 | ||
| Grand Prix Columbus 2004 (DST limited) | starting rating: 1439 | |||
| round | table | opponent (rating) | result | Δrating |
| 2sealed | 205 | Kasper, Matthew (1544) | Lost 0-2 | -161423 |
| 3sealed | 239 | Fahey, Sean (1499) | Won 2-0 | +191442 |
| 4sealed | 142 | Plance, James (1500) | Won 2-0 | +191461 |
| 5sealed | 112 | Zimmerman, Nathan (1536) | Lost 1-2 | -171444 |
| 6sealed | 122 | Bongiovanni, Mauro (1682) | Lost 0-2 | -131431 |
| top | average opponent: 1552record: 2-3 | new rating: 1431 | ||
| Grand Prix Kansas City 2003 (MRD limited) | starting rating: 1462 | |||
| round | table | opponent (rating) | result | Δrating |
| 3sealed | 15 | Price, Lance (1536) | Won 2-0 | +201482 |
| 4sealed | 41 | Jenniges, Nick (1500) | Lost 1-2 | -181464 |
| 5sealed | 92 | Kastle, Darwin (1858) | Draw 1-1 | +71471 |
| 6sealed | 73 | Thompson-Exner, Gavin (1533) | Lost 0-2 | -171454 |
| 7sealed | 99 | Mohmand, Mohammad (1520) | Draw 1-1 | +11455 |
| 8sealed | 88 | Tiernan, Peter (1538) | Lost 0-2 | -161439 |
| top | average opponent: 1581record: 1-3-2 | new rating: 1439 | ||
| Grand Prix Detroit 2003 (Onslaught block) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1block | 4 | Cornwall, Gary (1500) | Lost 0-1 | -181482 |
| 2block | 218 | King, Bill (1483) | Lost 0-2 | -181464 |
| 3block | 244 | Sweet, James (1464) | Won 2-0 | +181482 |
| 4block | 253 | Chapman, Jonny (1394) | Lost 1-2 | -201462 |
| top | average opponent: 1460record: 1-3 | new rating: 1462 | ||