Sania Mirza beat home favourite Tamarine Tanasugarn 7-5, 6-4 to move into the semifinals of the Pattaya Open on Friday.
However, Caroline Wozniacki was upset by eighth-seeded Magdalena Rybarikova in the quarterfinals, falling 6-4, 6-1.
After a tough opening set, Sania Mirza came back strong in the second set to take it 6-4.
Wozniacki, who had also struggled against Australian Open junior champion Ksenia Pervak earlier, made a disappointing start by conceding the opening game when Rybarikova fired a winning forehand down the line.
Twelfth-ranked Wozniacki failed to convert any of four break points in the next game, and then had to fight off two break points at 3-1 and another at 4-2 as the eighth-seeded Slovak continued to place her under pressure.
Serving well with three aces to hold for 5-3, Rybarikova constructed her points well and attacked at the right moments, and after breaking serve again to begin the second set she looked increasingly in command as Wozniacki's game deteriorated badly.
California: Top-seeded American Andy Roddick reached the quarterfinals of the $600,000 hardcourt SAP Open on Thursday with a 6-3, 7-6 (7/3) victory over tenacious Latvian Ernests Gulbis.
After cruising through the first set, Roddick found the second tougher as Gulbis stretched the match
Argentinian Juan Martin del Potro and American James Blake also advanced.
Li happy with progress
PARIS: Chinese Li Na said she was hoping to put injury behind her after losing 6-0, 3-6, 6-2 to Jelena Jankovic in Round 2 of the WTA Paris Open on Thursday. Agencies