MASON – The return of Kim Clijsters
took a giant leap forward on Thursday when the Belgian scored an upset, but she wasn’t the only newsmaker on the day as both Serena and Venus Williams
were ousted from the 2009 Western & Southern Financial Group Women’s Open.
Clijsters, the 2005 US Open champion and a former World No. 1, defeated No. 6 Svetlana Kuznetsova
6-4 4-6 6-2 on Thursday afternoon. It was the first three set match since Clijsters has returned to tennis after retiring in 2007 and having a baby in early 2008.
“To be honest with you, I knew that I wasn't gonna I worked really hard on my fitness, and I knew that wasn't gonna be a key out there for me today,” Clijsters said. “It was obviously the level, and my tennis felt like was the biggest key.”
The second seed, Serena Williams was taken out by another player who is a mom. Sybille Bammer
defeated Williams 7-5 6-4.
“I was nervous today,” Bammer said. “I just tried to come into the rallies and make her play, and this worked.”Flavia Pennetta
, the 14th seed, continued her incredible run this summer, pushing her winning streak to 14 with a 7-6(2) 6-4 win over No. 3 Venus Williams.
“I'm really, really happy,” Pennetta said. “Of course my confidence now it's perfect, you know. It's always when you win a lot of matches like this you believe more in yourself.”
Pennetta would move into the Top 10 with a win in Friday quarterfinals, which would make her the first Italian player to ever crack the Top 10.
Fourth-ranked Elena Dementieva
picked up a 6-4 6-4 win over Sonara Cirstea
to reach the quarterfinals, while Caroline Wozniacki
advanced after just three games with Melinda Czink
retired with a back injury.Daniela Hantuchova
, a former semifinalist in Cincinnati, outlasted Vera Zvonareva
7-6(6) 0-6 7-6(5) in 2:50.
In a match featuring a pair of Top 10 players, No. 5 Jelena Jankovic
downed No. 9 Victoria Azarenka
Here's a look at Thursday results (through 7 p.m.): SINGLES THIRD ROUND
 Dinara Safina (RUS) vs Shuai Peng (CHN)
Sybille Bammer (AUT) d  Serena Williams (USA) 75 64
 Flavia Pennetta (ITA) d  Venus Williams (USA) 76(2) 64
 Elena Dementieva (RUS) d Sonara Cirstea (ROU) 64 64
 J Jankovic (SRB) d  V Azarenka (BLR) 75 76(4)
[WC] KC Clijsters (BEL) d  S Kuznetsova (RUS) 64 46 62
D Hantuchova (SVK) d  V Zvonareva (RUS) 76(6) 06 76(5)
 C Wozniacki (DEN) d M Czink (HUN) 30 ret. (back)DOUBLES SECOND ROUND
(7) Nuria Llagostera Vives (ESP) / Maria Jose Sanchez Martinez (ESP) d Maria Kirilenko (RUS) / Elena Vesnina (RUS) 64 62
Akgul Amanmuradova (UZB) / Monica Niculescu (ROU) vs Alona Bondarenko (UKR) / Kateryna Bondarenko (UKR)DOUBLES QUARTERFINAL ROUND
 Cara Black (ZIM) / Luezel Huber (USA) vs  Bethanie Mattek-Sands (USA) / Nadia Petrova (RUS)
 Virginia Ruano Pascual (ESP) / Jie Zheng (CHN) d  Daniela Hantuchova (SVK) / Ai Sugiyama (JPN) walkover