Katerina Siniakova vs. Mary Stoiana — Osaka Open 2026 Quarterfinal Match Report. It has been more than a year since Katerina Siniakova last played in a singles semifinal. On Friday, the doubles world No. 1 made sure that wait finally came to an end. The Czech defeated American qualifier Mary Stoiana 6-1, 6-2 in the … Continue reading Siniakova Ends Singles Semifinal Wait as Stoiana’s Japan Open Run Hits a Wall