| Tournament | Round | Ivor Zetler | Ethel Collins |
| 25.01.1998 City of Sydney International Masters (NSW) | 14 | 375 | 305 |
| 25.01.1998 City of Sydney International Masters (NSW) | 15 | 373 | 332 |
| 25.01.1998 City of Sydney International Masters (NSW) | 16 | 300 | 395 |
| 05.04.1999 Australian Championships (NSW) | 1 | 429 | 355 |
| Head-to-head after 4 games | 3 | 1 | |
| Average score | 369.25 | 346.75 | |
| Spread: | 90 | -90 | |