| 1443.6 | 1444 | 20 | 20 | Van Der Merwe, W (Willem) | | GSV | 1316.5 | 1309 | Hoerskool Drie Riviere Open 08 March 2025 (D) | 2 | 2025-03-08 | S | W | 1 | 0.69 | 0.31 | 5.1 | 0.7 | 0.3 | 6 |
| 1415.8 | 1414.5 | 20 | 20 | Van Der Merwe, W (Willem) | | GSV | 1235.2 | 1234.5 | Laerskool Midvaal Chess Open Section 2024 (D) | 3 | 2024-02-10 | S | B | 0 | 0.67 | -0.67 | -11.1 | 0.67 | -0.67 | -13.4 |
| 1286.8 | 1296.1 | 20 | 20 | Van Der Merwe, W (Willem) | | GSV | 1276.9 | 1260 | Valia's Chess Tournament 2023 (D) | 4 | 2023-05-06 | S | B | 1 | 0.47 | 0.53 | 8.8 | 0.5 | 0.5 | 10 |
| 1277.3 | 1290.4 | 20 | 20 | Van Der Merwe, W (Willem) | | GSV | 1365 | 1362.7 | Laerkool Midvaal Chess Open 2023 (D) | 2 | 2023-01-28 | S | W | 0 | 0.44 | -0.44 | -7.3 | 0.46 | -0.46 | -9.2 |
