Brostoff, Jonathan
Current rating: 1908 (#548)
Record: 66-35-1 (GP) / 3-4 (professional)
| Grand Prix Madison 2019 (WAR limited) | starting rating: 1845 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 114 | Johnston, Brice (1448) | Won 2-0 | +111856 |
| 2sealed | 84 | Horkley, Ben (1525) | Won 2-0 | +131869 |
| 3sealed | 213 | Robinson, Jed (1543) | Lost 1-2 | -241845 |
| 4sealed | 254 | Howitt, Josh (1549) | Lost 1-2 | -231822 |
| 5sealed | 326 | Sletten, Andrew (1503) | Won 2-1 | +121834 |
| 6sealed | 253 | Roy, Anjon (1609) | Won 2-0 | +141848 |
| 7sealed | 162 | Stankey, Matt (1741) | Won 2-0 | +161864 |
| 8sealed | 115 | Duelfer, Matthew (1612) | Won 2-1 | +131877 |
| 9sealed | 85 | Strasler, Noah (1630) | Won 2-1 | +141891 |
| 10draft | 45 | DeGraff, Ian (1629) | Lost 1-2 | -231868 |
| 11draft | 89 | Kowal, Brian (1743) | Lost 1-2 | -201848 |
| 12draft | 30 | Beardsley, Jordan (1560) | Won 2-1 | +131861 |
| 13draft | 63 | Do, Dzi (1653) | Won 2-0 | +141875 |
| 14draft | 74 | Cloonan, Brian (1601) | Won 2-1 | +131888 |
| 15draft | 16 | Troha, Dan (1973) | Won 2-0 | +201908 |
| top | average opponent: 1621record: 11-4 | new rating: 1908 | ||
| Grand Prix Minneapolis 2018 (M19 limited) | starting rating: 1780 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 158 | Ramos, Joel (1500) | Won 2-1 | +131793 |
| 2sealed | 148 | Smrecek, Kade (1482) | Won 2-0 | +121805 |
| 3sealed | 106 | Pressman, Isaiah (1540) | Won 2-0 | +141819 |
| 4sealed | 52 | Hendriks, Thomas (2031) | Won 2-0 | +211840 |
| 5sealed | 79 | Sullivan, Adrian (1799) | Lost 0-2 | -181822 |
| 6sealed | 99 | Bogdanov, Dennis (1703) | Won 2-0 | +151837 |
| 7sealed | 74 | Michel, Gregory (2004) | Won 2-1 | +211858 |
| 8sealed | 41 | Carvalho, Marcio (2202) | Lost 1-2 | -121846 |
| 9sealed | 98 | Allhiser, Bradley (1594) | Lost 0-2 | -221824 |
| 10draft | 306 | Boulet, Drue (1682) | Won 2-0 | +151839 |
| 11draft | 306 | Sullivan, John (1543) | Won 2-0 | +131852 |
| 12draft | 307 | Bruni, Dante (1691) | Lost 1-2 | -211831 |
| 13draft | 270 | Maurer, Joshua (1627) | Won 2-0 | +151846 |
| 14draft | 317 | Dezani, Jeremy (2059) | Won 2-0 | +211867 |
| 15draft | 292 | Forgus, Jim (1634) | Lost 0-2 | -221845 |
| top | average opponent: 1739record: 10-5 | new rating: 1845 | ||
| Grand Prix Milwaukee 2016 (KLD limited) | starting rating: 1721 | |||
| round | table | opponent (rating) | result | Δrating |
| 3sealed | 41 | Semeyn, Jonathan (1472) | Won 2-0 | +141735 |
| 4sealed | 104 | Bursavich, Austin (1812) | Lost 0-2 | -171718 |
| 5sealed | 188 | Dedrick, John (1568) | Lost 1-2 | -211697 |
| 6sealed | 243 | Qu, Brendon (1586) | Won 2-1 | +161713 |
| 7sealed | 227 | Mann, Samir (1544) | Won 2-0 | +151728 |
| 8sealed | 170 | Lavrenz, Joe (1720) | Won 2-0 | +181746 |
| 9sealed | 97 | Lu, Xiaoshi (1901) | Won 2-1 | +211767 |
| 10draft | 14 | Carvill, Adam (1569) | Won 2-1 | +141781 |
| 11draft | 58 | Hu, Haibing (2002) | Won 2-0 | +221803 |
| 12draft | 58 | Huelsman, Stephen (1685) | Won 2-1 | +161819 |
| 13draft | 104 | Nowakowski, Jack (1685) | Lost 0-2 | -201799 |
| 15draft | 33 | Beydler, Ben (1736) | Lost 0-2 | -191780 |
| top | average opponent: 1690record: 8-4 | new rating: 1780 | ||
| Grand Prix Madison 2015 (BFZ limited) | starting rating: 1726 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 555 | Muskovitz, Jared (1479) | Won 2-0 | +141740 |
| 2sealed | 110 | Caldwell, Ron (1518) | Won 2-0 | +141754 |
| 3sealed | 246 | Andrews, Joey (1630) | Won 2-0 | +161770 |
| 4sealed | 170 | TerHaar, Aaron (1554) | Lost 1-2 | -221748 |
| 5sealed | 325 | Tryzbiak, Ryan (1489) | Won 2-0 | +131761 |
| 6sealed | 199 | Fyfe, Max (1556) | Lost 1-2 | -221739 |
| 7sealed | 238 | Myatt, Jason (1733) | Lost 1-2 | -181721 |
| top | average opponent: 1566record: 4-3 | new rating: 1721 | ||
| Grand Prix Indianapolis 2013 (RTR limited) | starting rating: 1698 | |||
| round | table | opponent (rating) | result | Δrating |
| 2sealed | 20 | Kinkade, Eben (1518) | Won 2-0 | +141712 |
| 3sealed | 129 | Wendling, Andrew (1536) | Won 2-0 | +151727 |
| 4sealed | 101 | Scott-Vargas, Luis (1897) | Won 2-1 | +211748 |
| 5sealed | 255 | Odorizzi, Christopher (1722) | Lost 0-2 | -181730 |
| 6sealed | 59 | Wyant, Aaron (1595) | Lost 0-2 | -211709 |
| 7sealed | 93 | Gardner, Joe A (1579) | Won 2-0 | +161725 |
| 8sealed | 53 | Moulton, Jesse (1597) | Won 2-0 | +161741 |
| 9sealed | 85 | Krumb, Michael (1937) | Lost 1-2 | -151726 |
| top | average opponent: 1673record: 5-3 | new rating: 1726 | ||
| Grand Prix Chicago 2012 (modern) | starting rating: 1700 | |||
| round | table | opponent (rating) | result | Δrating |
| 3modern | 152 | Ragusa, Christopher (1535) | Lost 0-2 | -211679 |
| 4modern | 238 | Kunz, Mason (1519) | Lost 1-2 | -211658 |
| 5modern | 392 | Hall, Christopher L (1452) | Lost 1-2 | -221636 |
| 6modern | 391 | Wisniewski, Philip (1481) | Won 2-1 | +151651 |
| 7modern | 273 | Kelly, Daniel (1525) | Won 2-1 | +161667 |
| 8modern | 188 | Bruce, Evan (1522) | Won 2-0 | +151682 |
| 9modern | 167 | Taylor, Zachary (1534) | Won 2-0 | +161698 |
| top | average opponent: 1510record: 4-3 | new rating: 1698 | ||
| Grand Prix Minneapolis 2012 (AVR standard) | starting rating: 1556 | |||
| round | table | opponent (rating) | result | Δrating |
| 1standard | 84 | Greeno, Cody (1500) | Won 2-1 | +171573 |
| 2standard | 212 | Hanford, Casey J (1537) | Lost 1-2 | -191554 |
| 3standard | 298 | Reynolds, Christina (1482) | Won 2-0 | +171571 |
| 4standard | 293 | Kraus, Jaime (1516) | Won 2-1 | +171588 |
| 5standard | 190 | Smaker, Nathan (1494) | Won 2-1 | +161604 |
| 6standard | 65 | Moore, Tanner (1552) | Won 2-1 | +171621 |
| 7standard | 77 | Napper, Josh (1613) | Won 2-0 | +181639 |
| 8standard | 40 | Lynn, Brian (1573) | Won 2-0 | +171656 |
| 9standard | 10 | Tinney, Bradley (1733) | Draw 1-1 | +11657 |
| 10standard | 20 | Bentson, Daniel (1575) | Won 2-1 | +171674 |
| 11standard | 10 | Alshanski, Scott (1611) | Won 2-1 | +171691 |
| 12standard | 7 | Laehn, Taylor (1783) | Lost 0-2 | -171674 |
| 13standard | 17 | Patwell, David (1630) | Won 2-0 | +181692 |
| 14standard | 10 | Sharfman, David (1828) | Lost 1-2 | -161676 |
| 15standard | 20 | Ochoa, David (1985) | Won 2-1 | +241700 |
| top | average opponent: 1628record: 11-3-1 | new rating: 1700 | ||
| Grand Prix Minneapolis 2009 (ZEN limited) | starting rating: 1507 | |||
| round | table | opponent (rating) | result | Δrating |
| 2sealed | 169 | Jewell, Andrew (1517) | Won 2-0 | +181525 |
| 3sealed | 88 | Coqueiro, Rafael S (1640) | Won 2-0 | +201545 |
| 4sealed | 109 | Turtenwald, Owen (1789) | Lost 0-2 | -131532 |
| 5sealed | 137 | Klink, Dave (1519) | Won 2-0 | +171549 |
| 6sealed | 136 | Artenbach, Anthony (1552) | Won 2-0 | +181567 |
| 7sealed | 68 | Fruth, Kurt (1657) | Lost 0-2 | -161551 |
| 8sealed | 127 | Sosko, Darin J (1555) | Won 2-1 | +181569 |
| 9sealed | 97 | Rocha, Jerret (1644) | Won 2-1 | +191588 |
| 10draft | 23 | Piazza, Brett (1753) | Won 1-0 | +211609 |
| 11draft | 34 | Vargas, Andrew (1831) | Lost 0-2 | -141595 |
| 12draft | 32 | Laehn, Taylor (1501) | Lost 1-2 | -191576 |
| 13draft | 63 | Tanner, Kasey (1552) | Won 2-0 | +171593 |
| 14draft | 42 | Kaplan, Louis (1598) | Lost 1-2 | -181575 |
| 15draft | 3 | Hellenbrand, Seth (1507) | Lost 0-2 | -191556 |
| top | average opponent: 1615record: 8-6 | new rating: 1556 | ||
| Grand Prix Indianapolis 2008 (SHM limited) | starting rating: 1487 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 220 | Byrum, Danielle (1500) | Won 2-1 | +181505 |
| 2sealed | 55 | Holland, Kitt (1526) | Lost 0-2 | -181487 |
| 3sealed | 281 | Silbernick, Josh (1507) | Lost 1-2 | -171470 |
| 4sealed | 398 | Wisnor, Steven (1480) | Won 2-0 | +181488 |
| 5sealed | 338 | Soungpanya, Jinda A (1499) | Won 2-1 | +181506 |
| 6sealed | 270 | Finley, Brian (1520) | Won 2-0 | +181524 |
| 7sealed | 145 | Askoul, Basem (1535) | Won 2-0 | +191543 |
| 8sealed | 73 | Byrd, Wes T (1541) | Lost 0-2 | -181525 |
| 9sealed | 124 | Burroughs, Ben (1541) | Lost 0-2 | -181507 |
| top | average opponent: 1517record: 5-4 | new rating: 1507 | ||
| Pro Tour Chicago 1999 (extended) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1extended | 64 | Bede, Robert (1500) | Lost 0-2 | -181482 |
| 2extended | 169 | Fertman, Alexander (1481) | Won 2-0 | +181500 |
| 3extended | 101 | Price, David (1668) | Lost 1-2 | -151485 |
| 4extended | 106 | Jansen, Patrick (1480) | Lost 0-2 | -181467 |
| 5extended | 142 | Polin, Justin (1449) | Won 2-0 | +181485 |
| 6extended | 113 | Strong, Adam (1485) | Won 2-1 | +181503 |
| 7extended | 90 | Canu, Franck (1622) | Lost 0-2 | -161487 |
| top | average opponent: 1527record: 3-4 | new rating: 1487 | ||