Herrdum, Kai
Current rating: 1539
Record: 4-3 (GP) / 3-4 (professional)
| Grand Prix Brussels 2020 (pioneer) | starting rating: 1510 | |||
| round | table | opponent (rating) | result | Δrating |
| 1pioneer | 323 | Barbieri, Diego (1459) | Won 2-0 | +171527 |
| 2pioneer | 56 | Las Heras Aixandri, Guillem (1522) | Won 2-1 | +181545 |
| 3pioneer | 12 | Micheletti, Natan (1683) | Won 2-1 | +211566 |
| 4pioneer | 98 | Stihle, Julien (1964) | Lost 0-2 | -121554 |
| 5pioneer | 341 | Johanson, Olaf-Carlin (1536) | Won 2-1 | +181572 |
| 6pioneer | 193 | Zurlo, Claudio (1543) | Lost 1-2 | -181554 |
| 7pioneer | 170 | Del Pivo, Marco (1757) | Lost 1-2 | -151539 |
| average opponent: 1638record: 4-3 | new rating: 1539 | |||
| Players Tour Brussels 2020 (pioneer) | starting rating: 1500 | |||
| round | table | opponent (rating) | result | Δrating |
| 1draft | 178 | Kohn, Michel (1757) | Lost 1-2 | -131487 |
| 2draft | 188 | Klimczyk, Wojtek (1659) | Won 2-0 | +211508 |
| 3draft | 146 | Ucuzal, Batuhan (1840) | Won 2-0 | +241532 |
| 4pioneer | 81 | Klein, Fabian (1804) | Lost 0-2 | -141518 |
| 5pioneer | 108 | De Jesus Alves Pereira, Gabriel (1526) | Won 2-0 | +191537 |
| 6pioneer | 67 | Telarov, Aleksa (1676) | Lost 0-2 | -161521 |
| 7pioneer | 113 | Depraz, Jean-Emmanuel (1926) | Lost 0-2 | -111510 |
| average opponent: 1741record: 3-4 | new rating: 1510 | |||