It's third round action at the WTA Charleston 2013 on Thursday with top two seeds Serena Williams and Caroline Wozniacki to take court today.
Wozniacki, who had an easy second round win over Silvia Soler Espinosa, will now take on German wild-card Andrea Petkovic in her third round match at the Billie Jean King court. Petkovic defeated Taylor Townsend in her first round and then sent out Vania King in her previous match.
Following this match will be the top seeded Williams, who plays fellow American and qualifier Mallory Burdette. Burdette upset the 15th seeded Sabine Lisicki in her second round match but will need an extraordinary performance against the defending champion and the in-form Williams.
In other third round matches, 12th seeded Varvara Lepchenko plays Venus Williams, seeded five in the competition. Williams needed a tough three-setter against Monica Puig to make it to the third round after an opening round bye.
Sixth seeded Lucie Safarova will then be up against Sorana Cirstea of Romania, seeded 11th, before third seeded Samantha Stosur takes court. The Australian Stosur will be up against Canadian qualifier Eugenie Bouchard. Bouchard sent the 16th seeded British player Laura Robson out of the tournament in the previous round.
Here’s the WTA Charleston 2013 Order of Play for Thursday, April 4 (GMT)
BILLIE JEAN KING
Starting at 3.00 pm
[WC] Andrea Petkovic (GER) v [WC] Caroline Wozniacki (DEN) 
Not Before 5.00 pm
Serena Williams (USA)  v [Q] Mallory Burdette (USA)
Varvara Lepchenko (USA)  v Venus Williams (USA) 
Sorana Cirstea (ROU)  v Lucie Safarova (CZE) 
Not Before 11.00 pm
[Q] Eugenie Bouchard (CAN) v Samantha Stosur (AUS) 
Andrea Hlavackova (CZE) / Liezel Huber (USA)  v Hao-Ching Chan (TPE) / Olga Govortsova (BLR)
Starting at 3.00 pm
[WC] Bethanie Mattek-Sands (USA) v Madison Keys (USA)
Stefanie Voegele (SUI) v Julia Goerges (GER) 
[Q] Jessica Pegula (USA) v Jelena Jankovic (SRB) 
Julia Goerges (GER) / Yaroslava Shvedova (KAZ)  v Megan Moulton-Levy (USA) / Shuai Zhang (CHN)
Here’s how to watch the WTA Charleston 2013 free online: