Grudzina, John
Current rating: 1627
Record: 40-33-3
| Grand Prix New Jersey 2014 (legacy) | starting rating: 1551 | |||
| round | table | opponent (rating) | result | Δrating |
| 1legacy | 306 | Anderegg, Morgan (1498) | Won 2-0 | +171568 |
| 2legacy | 170 | Doepker, Mitchell (1518) | Won 2-0 | +171585 |
| 3legacy | 61 | Crawford, Ross (1538) | Won 2-0 | +181603 |
| 4legacy | 3 | DiTizio, Nicholas (1508) | Won 2-1 | +161619 |
| 5legacy | 19 | Oransky, Sam (1506) | Lost 1-2 | -201599 |
| 6legacy | 108 | Ell, Matthew (1505) | Won 2-0 | +161615 |
| 7legacy | 73 | Azzano, Douglas (1931) | Lost 1-2 | -121603 |
| 8legacy | 128 | Fabiano, Gerard (1891) | Won 2-1 | +231626 |
| 9legacy | 101 | Zhang, Bo [USA] (1571) | Won 2-1 | +171643 |
| 10legacy | 177 | Roberts, Shawn (1595) | Won 2-1 | +171660 |
| 11legacy | 135 | Gottlieb, Bryan (1924) | Lost 1-2 | -131647 |
| 12legacy | 134 | Housman, Myles (1691) | Lost 1-2 | -181629 |
| 13legacy | 182 | Crist, Jason (1590) | Won 2-0 | +181647 |
| 14legacy | 118 | Whitehurst, Clinton (1555) | Lost 0-2 | -201627 |
| top | average opponent: 1630record: 9-5 | new rating: 1627 | ||
| Grand Prix Providence 2011 (legacy) | starting rating: 1557 | |||
| round | table | opponent (rating) | result | Δrating |
| 2legacy | 26 | Eldredge, Will (1503) | Lost 1-2 | -191538 |
| 3legacy | 109 | Guild, Barret W (1501) | Won 2-1 | +171555 |
| 4legacy | 117 | S., Bobby (1522) | Lost 1-2 | -181537 |
| 5legacy | 218 | Goodrich, Richard (1502) | Lost 1-2 | -191518 |
| 6legacy | 187 | Kurth, Lloyd (1481) | Won 2-0 | +171535 |
| 7legacy | 158 | Knaack, Aaron (1465) | Won 2-0 | +171552 |
| 8legacy | 114 | Obrien, David (1525) | Lost 0-2 | -181534 |
| 9legacy | 88 | Race, Joshua A (1521) | Won 2-0 | +171551 |
| top | average opponent: 1502record: 4-4 | new rating: 1551 | ||
| Grand Prix Columbus 2010 (legacy) | starting rating: 1562 | |||
| round | table | opponent (rating) | result | Δrating |
| 2legacy | 423 | Britton, Steven (1516) | Lost 1-2 | -191543 |
| 3legacy | 553 | Defazio, David (1498) | Won 2-0 | +181561 |
| 4legacy | 550 | Lynn, Michael (1517) | Won 2-0 | +171578 |
| 5legacy | 455 | Hinojosa, Rolaund (1538) | Draw 1-1 | -11577 |
| 6legacy | 487 | Lemon, Thomas (1518) | Won 2-0 | +171594 |
| 7legacy | 452 | Aleksandravicius, John (1525) | Lost 1-2 | -191575 |
| 8legacy | 495 | Johnson, Jason (1584) | Lost 0-2 | -181557 |
| top | average opponent: 1528record: 3-3-1 | new rating: 1557 | ||
| Grand Prix Washington DC 2010 (ROE standard) | starting rating: 1587 | |||
| round | table | opponent (rating) | result | Δrating |
| 2standard | 166 | Rowe, Jonathan (1516) | Lost 1-2 | -201567 |
| 3standard | 311 | Martinez, Andre (1499) | Won 2-0 | +171584 |
| 4standard | 135 | Yaris, William (1519) | Won 2-1 | +171601 |
| 5standard | 98 | Kailing, Michael (1544) | Lost 1-2 | -191582 |
| 6standard | 184 | Blystone, David (1484) | Lost 0-2 | -201562 |
| top | average opponent: 1512record: 2-3 | new rating: 1562 | ||
| Grand Prix Indianapolis 2008 (SHM limited) | starting rating: 1566 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 126 | Hagerty, Brian (1500) | Won 2-0 | +171583 |
| 2sealed | 232 | Thomas, David S (1542) | Won 2-1 | +171600 |
| 3sealed | 98 | Succan, Ryan (1572) | Won 2-0 | +171617 |
| 4sealed | 94 | Tedeschi, Michael (1654) | Won 2-0 | +191636 |
| 5sealed | 48 | Webb, Taylor (1754) | Lost 0-2 | -161620 |
| 6sealed | 140 | Saito, Tomoharu (1852) | Lost 1-2 | -141606 |
| 7sealed | 156 | Byrd, Wes T (1522) | Lost 0-2 | -191587 |
| top | average opponent: 1628record: 4-3 | new rating: 1587 | ||
| Grand Prix Philadelphia 2008 (extended) | starting rating: 1533 | |||
| round | table | opponent (rating) | result | Δrating |
| 2extended | 49 | Breedwell, Brian O (1518) | Lost 0-2 | -181515 |
| 3extended | 320 | Renner, Teo V (1500) | Won 2-0 | +171532 |
| 4extended | 170 | Moore, Timothy S (1504) | Won 2-0 | +181550 |
| 5extended | 193 | Innace, Michael (1476) | Won 2-0 | +161566 |
| 6extended | 112 | Moir, Ben (1522) | Lost 0-2 | -181548 |
| 7extended | 142 | Thanakit, Isara (1485) | Won 2-1 | +161564 |
| 8extended | 66 | Chamberlain, Bryan (1565) | Won 2-0 | +181582 |
| 9extended | 78 | Siu, Brian (1655) | Lost 1-2 | -161566 |
| top | average opponent: 1528record: 5-3 | new rating: 1566 | ||
| Grand Prix Montreal 2007 (Time Spiral block) | starting rating: 1515 | |||
| round | table | opponent (rating) | result | Δrating |
| 2block | 152 | Ragsdale, Adam (1569) | Won 2-1 | +191534 |
| 3block | 24 | LaDouceur, Christian (1546) | Won 2-0 | +181552 |
| 4block | 38 | Sauerborn, Moritz (1688) | Draw 1-1 | +21554 |
| 5block | 51 | Smith, Ian J (1556) | Won 2-1 | +181572 |
| 6block | 25 | Cox, Benjamin (1556) | Lost 1-2 | -181554 |
| 7block | 65 | Brichta, Jean-Paul (1526) | Won 2-0 | +181572 |
| 8block | 39 | Samms, Phil (1419) | Lost 0-0 | -211551 |
| 9block | 69 | Luk, Andrew (1556) | Lost 0-0 | -181533 |
| top | average opponent: 1552record: 4-3-1 | new rating: 1533 | ||
| Grand Prix Columbus 2007 (legacy) | starting rating: 1511 | |||
| round | table | opponent (rating) | result | Δrating |
| 2legacy | 65 | Estep, James (1518) | Won 2-1 | +181529 |
| 3legacy | 81 | Crummel, Mike (1535) | Won 2-1 | +181547 |
| 4legacy | 11 | Thompson, Gerry (1766) | Draw 1-1 | +41551 |
| 5legacy | 51 | Graves, Robert (1500) | Lost 0-2 | -191532 |
| 6legacy | 123 | Bowab, Parker (1573) | Lost 0-2 | -171515 |
| top | average opponent: 1578record: 2-2-1 | new rating: 1515 | ||
| Grand Prix Philadelphia 2005 (legacy) | starting rating: 1468 | |||
| round | table | opponent (rating) | result | Δrating |
| 1legacy | 26 | Gottehrer, Jonathan (1500) | Won 2-0 | +191487 |
| 2legacy | 20 | London Wilkinson, Akida (1518) | Won 2-0 | +191506 |
| 3legacy | 16 | Stolze, Philip (1500) | Lost 1-2 | -191487 |
| 4legacy | 142 | Monahan, Sean (1503) | Won 2-1 | +191506 |
| 5legacy | 91 | Coffey, Josh (1537) | Lost 1-2 | -181488 |
| 6legacy | 94 | Toms, Bennett (1522) | Won 2-1 | +191507 |
| 7legacy | 86 | Zajdner, Mark (1702) | Won 2-1 | +211528 |
| 8legacy | 35 | Jarvis, Aaron (1537) | Lost 0-2 | -171511 |
| top | average opponent: 1540record: 5-3 | new rating: 1511 | ||
| Grand Prix Boston 2005 (extended) | starting rating: 1466 | |||
| round | table | opponent (rating) | result | Δrating |
| 1extended | 122 | Littman, Fai (1500) | Lost 1-2 | -171449 |
| 2extended | 248 | Murray, Bill (1482) | Won 2-0 | +181467 |
| 3extended | 186 | Johnston, Joel (1500) | Won 2-1 | +191486 |
| 4extended | 210 | Patterson, Jason (1507) | Lost 1-2 | -181468 |
| top | average opponent: 1497record: 2-2 | new rating: 1468 | ||
| Grand Prix Philadelphia 2002 (ONS rochester) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 44 | Kolbig, Kent (1500) | Lost 1-2 | -181482 |
| 2sealed | 154 | DeTora, Melissa (1603) | Lost 0-2 | -161466 |
| top | average opponent: 1551record: 0-2 | new rating: 1466 | ||