| Tournament | Round | Ros Gibbons | Zina Costanzo |
| 09.08.1998 NSW/Victoria Border Challenge Wagga Wagga (NSW) | 8 | 407 | 398 |
| 21.01.1999 City of Sydney Masters (NSW) | 3 | 392 | 241 |
| 05.04.1999 Australian Championships (NSW) | 10 | 394 | 372 |
| 01.08.1999 Winter Masters (NSW) | 4 | 438 | 313 |
| Head-to-head after 4 games | 4 | 0 | |
| Average score | 407.75 | 331 | |
| Spread: | 307 | -307 | |