The quarterfinal participants for the Credit One Charleston Open were decided on Thursday, featuring victories from three of the top four seeded players and a significant surprise as Anna Kalinskaya triumphed over Australian Open champion Madison Keys.
In the evening session at Credit One Stadium, Kalinskaya defeated No. 2 seed Keys with a score of 6-2, 6-4. She capitalized on an uncharacteristically inconsistent performance from Keys, who is ranked No. 5 globally. This win marks Kalinskaya`s first Top 10 victory in ten months and propels her into her second quarterfinal appearance of the season. Keys struggled with 40 unforced errors, won less than half of her first-serve points, and only converted one out of eight break point opportunities. These factors contributed to Kalinskaya evening their head-to-head record to 1-1.
Charleston: Draws | Scores | Order of play
However, Kalinskaya`s victory wasn`t the only unexpected result in the Round of 16. Continue reading for more highlights from Thursday in Charleston.
Kalinskaya `Needed This` After a Difficult Start: Kalinskaya, who reached a career-high ranking of No. 11 last October following a successful 2025 season with finals appearances in Dubai and Berlin, and the second week of two Grand Slams, had not replicated that form in the initial months of 2025. After missing the Australian Open due to illness, she came to Charleston with a 4-7 season record and only one instance of consecutive match wins at a tournament in Singapore in February, where she withdrew in the semifinals.
However, after her 11th career victory against a Top 10 player by defeating Keys, the 26-year-old expressed that this result was essential for her.
`This victory is particularly meaningful. I needed it to boost my confidence. My year began with some setbacks, but it feels great to be performing at a high level again,` she stated. `I believe the key tonight was varying the rhythm; I incorporated some drop shots, especially in the first set.`
`I aimed to avoid extended rallies because Madison is a formidable opponent with incredibly powerful shots. I focused on being aggressive on my serve, maintaining consistency, and dictating the level of play, which I believe was crucial.`
Kalinskaya is set to compete against Sofia Kenin, the 2020 Australian Open champion, in her next match. Kenin also caused an upset by defeating No. 5 seed Daria Kastkina in the evening`s final match, with scores of 6-3, 7-6(7).
Pegula Maintains Dominance: In contrast to some other top seeds facing challenges, No. 1 seed Pegula has been performing smoothly. After conceding only three games in her opening round, Pegula allowed just five games to Ajla Tomljanovic, securing her quarterfinal spot with a 6-3, 6-2 victory.
This match was significantly different from their previous encounter in the Austin semifinal last month, which Pegula won 6-1, 4-6, 6-3. In this match, Pegula won five consecutive games in the middle to gain a decisive lead.
Pegula will face Danielle Collins, the defending champion, in the quarterfinals, holding a perfect 6-0 record against her. Collins overcame a break deficit in both sets to defeat No. 11 seed Jelena Ostapenko 7-5, 6-3, marking her eighth consecutive victory in Charleston.
Zheng Advances, Alexandrova Overcomes Shnaider: Olympic champion Zheng Qinwen`s 13th successive clay-court victory was not straightforward. The No. 3 seed had to recover from a break down in the final set to defeat No. 13 seed Elise Mertens, 6-3, 3-6, 6-3.
Her next opponent will be No. 9 seed Ekaterina Alexandrova, who won against No. 6 seed Diana Shnaider with a score of 6-1, 6-2. Alexandrova, the Linz champion, ended a four-match losing streak with these two wins this week, following an eight-win streak that ended at the Qatar Total Open semifinals in February.
