Ai Sugiyama defeated Justine Henin 6-2 6-4 in the WTA Tour Championships round robin on carpet. The upset overturned the form book — Justine Henin came in leading the head-to-head 4–0, defending last year's quarter-final. Ai Sugiyama claimed a first win over Justine Henin in five meetings, narrowing the head-to-head to 4–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2006-08-28 | US Open | R32 | hard | Justine Henin | 4-6 6-1 6-0 |
| 2006-03-06 | Indian Wells | R16 | hard | Justine Henin | 6-2 6-1 |
| 2003-02-10 | Antwerp | QF | hard | Justine Henin | 6-2 6-4 |
| 2001-08-13 | Toronto | R32 | hard | Justine Henin | 6-4 7-6(5) |
Averages from each player's recent completed matches (20 vs 20). ATP, WTA & Challenger.