| 1412 | 1410.8 | 20 | 20 | Van Der Merwe, W (Willem) | | GSV | 1309.8 | 1307.2 | Eureka Open 2023 (F) | 5 | 2023-07-29 | S | W | 0 | 0.66 | -0.66 | -11 | 0.66 | -0.66 | -13.2 |
| 1383 | 1379 | 20 | 20 | Van Der Merwe, W (Willem) | | GSV | 1276.9 | 1260 | Valia's Chess Tournament 2023 (D) | 2 | 2023-05-06 | S | B | 0.5 | 0.58 | -0.08 | -1.3 | 0.6 | -0.1 | -2 |
| 1354 | 1341.9 | 20 | 20 | Van Der Merwe, W (Willem) | | GSV | 1365 | 1362.7 | Laerkool Midvaal Chess Open 2023 (D) | 3 | 2023-01-28 | S | W | 1 | 0.53 | 0.47 | 7.8 | 0.52 | 0.48 | 9.6 |
| 1410 | 1415 | 20 | 20 | Van Der Merwe, W (Willem) | | GSV | 1262.3 | 1277 | Eureka Open 2022 (G+H) | 3 | 2022-07-30 | S | B | 1 | 0.63 | 0.37 | 6.1 | 0.62 | 0.38 | 7.6 |
| 1114.8 | 1104.8 | 20 | 20 | Van Der Merwe, W (Willem) | | GSV | 1200 | 1200 | Midvaal Chess Open 2020 (D) | 5 | 2020-01-25 | S | W | 1 | 0.44 | 0.56 | 9.3 | 0.43 | 0.57 | 11.4 |
