Welch, Colin
Current rating: 1571
| Grand Prix Seattle-Tacoma 2012 (DKA limited) | starting rating: 1531 | |||
| round | table | opponent (rating) | result | Δrating |
| 2sealed | 134 | Ratanadawong, Jordan (1501) | Won 2-1 | +171548 |
| 3sealed | 144 | Nelson, Ray A (1537) | Lost 0-2 | -181530 |
| 4sealed | 192 | Lee, Paul (1448) | Won 2-1 | +171547 |
| 5sealed | 104 | Morales, Andrew (1536) | Won 2-0 | +171564 |
| 6sealed | 122 | Forner, Matthew (1676) | Won 2-0 | +201584 |
| 7sealed | 85 | Sahebjam, David (1539) | Won 2-1 | +181602 |
| 8sealed | 21 | Nguyen, James (1756) | Lost 0-2 | -161586 |
| 9sealed | 40 | Kovacs, Bryan J (1710) | Lost 0-2 | -151571 |
| top | average opponent: 1588record: 5-3 | new rating: 1571 | ||
| Grand Prix Portland 2010 (M11 limited) | starting rating: 1517 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 264 | Palke, Darrel (1500) | Won 2-0 | +181535 |
| 2sealed | 247 | Mirchel, Thomas (1500) | Lost 1-2 | -191516 |
| 3sealed | 213 | Alfaro, Joe (1483) | Won 2-0 | +171533 |
| 4sealed | 252 | Vollendorf, David (1517) | Won 2-1 | +181551 |
| 5sealed | 189 | Battisti, Eric (1543) | Won 2-1 | +181569 |
| 6sealed | 151 | Craft, Brian (1552) | Lost 1-2 | -181551 |
| 7sealed | 199 | Lambert, Kevin (1493) | Lost 1-2 | -191532 |
| 8sealed | 199 | Diamant, Michael (1518) | Lost 1-2 | -191513 |
| 9sealed | 155 | Christensen, John m (1487) | Won 2-0 | +181531 |
| top | average opponent: 1510record: 5-4 | new rating: 1531 | ||
| Grand Prix Oakland 2004 (DST limited) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1sealed | 74 | Froug, Andrew (1500) | Draw 1-1 | 01500 |
| 2sealed | 101 | Lam, John (1500) | Won 2-0 | +181518 |
| 3sealed | 70 | Vigderman, Constantine (1519) | Lost 1-2 | -181500 |
| 4sealed | 143 | Hom, Kevin (1498) | Won 2-1 | +181518 |
| 5sealed | 99 | Ramsey, Alan (1518) | Lost 0-2 | -181500 |
| 6sealed | 120 | Russo, Joseph (1499) | Lost 0-2 | -181482 |
| 7sealed | 104 | Johnson, Paul (1522) | Won 2-0 | +191501 |
| 8sealed | 82 | LaRue, Michael (1402) | Won 2-0 | +161517 |
| top | average opponent: 1495record: 4-3-1 | new rating: 1517 | ||