Twenty-one of 25 former champions were, had been, or would be ranked in the Top 20.
| year | Event | RND | Winner | Results |
|---|---|---|---|---|
| 2006 |
Generali Ladies Linz
Austria, Linz |
Championship | Vera Zvonareva |
6-4
6-6 |
| 2006 |
Zurich Open
Switzerland, Zurich |
Championship | Katarina Srebotnik |
6-3
7-5 |
| 2006 |
Porsche Tennis Grand Prix
Germany, Stuttgart |
Championship | Jelena Jankovic |
7-6
6-3 |
| year | Event | RND | Winner | Results |
|---|---|---|---|---|
| 2021 |
Heilbronn
|
1/8 | Philipp Kohlschreiber |
3-6
6-4 6-1 |
| 2021 |
Heilbronn
|
1/16 | Philipp Kohlschreiber |
6-4
6-3 |
| 2021 |
BMW Open by FWU
|
1/16 | Dominik Koepfer |
4-6
6-4 6-3 |
| 2021 |
Belgrade
|
1/8 | Damir Dzumhur |
6-4
6-3 |
| 2021 |
Belgrade
|
1/16 | Philipp Kohlschreiber |
5-7
6-4 2-6 |
