Maria Claudia Santos Santanna defeated Karen Castiblanco 6-2 6-2 in the Mogi Das Cruzes 10K round of 16 on clay. The upset overturned the form book — Karen Castiblanco came in leading the head-to-head 1–0. Maria Claudia Santos Santanna claimed a first win over Karen Castiblanco in two meetings, narrowing the head-to-head to 1–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2008-10-13 | Lima 10K | R32 | clay | Karen Castiblanco | 6-4 6-2 |