S. Sierra and C. McNally are level 1-1 in their head-to-head since 2018 over 2 matches.
| Surface | S. Sierra | C. McNally |
|---|---|---|
| Grass | 0 | 1 |
| Hard | 1 | 0 |
| Date | Winner | Score | Event |
|---|---|---|---|
| June 12, 2026 | C. McNally | 2 - 0 | Hertogenbosch · 1/8-finals · grass |
| Jan. 12, 2026 | S. Sierra | 2 - 1 | WTA Hobart · 1/16-finals · hard |