ORDER OF PLAY
(Play begins at 10am unless otherwise stated)
VICTOR KIAM STADIUM
ZHANG Shuai (CHN)  v Andrea PETKOVIC (GER)
Camila GIORGI (ITA) v Margarita GASPARYAN (RUS)
[WC] Kristie AHN (USA) v [Q] Jil TEICHMANN (SUI)
[WC] CoCo VANDEWEGHE (USA) v [LL] Anna BLINKOVA (RUS)
[Q] Fiona FERRO (FRA) v [LL] Viktorija GOLUBIC (SUI)
PERSHING SQUARE STADIUM
Katerina SINIAKOVA (CZE)  v WANG Yafan (CHN)
[Q] ZHU Lin (CHN) v Yulia PUTINTSEVA (KAZ) 
Karolina MUCHOVA (CZE)  v Viktoria KUZMOVA (SVK)
[LL] Laura SIEGEMUND (GER) v Mihaela BUZARNESCU (ROU)
[WC] Kristia AHN (USA) / Vania KING (USA) v DUAN Yingying (CHN) / Renata VORACOVA (CZE)
Desirae KRAWCZYK (USA) / Alicja ROSOLSKA (POL)  v Raluca OLARU (ROU) / YANG Zhaoxuan (CHN)
Alison VAN UYTVANCK (BEL) v [Q] Anastasia POTAPOVA (RUS)
Polona HERCOG (SLO) v Aliaksandra SASNOVICH (BLR) 
[Q] Magda LINETTE (POL) v [Q] Kaia KANEPI (EST)
Vikoria KUZMOVA (SVK) / Aliaksandra SASNOVICH (BLR) v CHAN Hao-Ching (TPE) / Latisha SHAN (TPE) 
(Play starts at 12pm)
Monique ADAMCZAK (AUS) / Storm SANDERS (AUS) v Darija JURAK (CRO) / María José MARTÍNEZ SÁNCHEZ (ESP) 
After suitable rest
[WC] HSIEH Su-Wei (TPE) / HSIEH Yu-Chieh (TPE) v Margarita GASPARYAN (RUS) / Monica NICULESCU (ROU)
Andrea Petkovic holds a 2-0 career head-to-head advantage over No.4 seed Zhang Shuai, with the most recent meeting between the pair coming at Wimbledon last year, where the German won in three sets over two hours.
Camila Giorgi recently made her seventh WTA Tour final in Washington but has lost in the first round at both Toronto and Cincinnati.
Margarita Gasparyan is searching for her first Top 100 hard court victory of 2019 and has a 1-1 career head-to-head record with the Italian, having met twice in Linz. Both matches went the distance.
Katerina Siniakova reached four hard court quarterfinals in 2018 but has failed to recapture that form this year, posting a 6-12 record on the surface.
She has faced Yafan Wang only once before, at the 2018 Shenzhen Open, where she won in straight sets.
Polona Hercog and Aliaksandra Sasnovich have faced off twice before. In both those meetings, the player who has won the first set has gone on to lose the match.
CoCo Vandeweghe played her first singles tournament of 2019 in San Jose at the end of July. Her return from injury was successful as she beat Marie Bouzkova before posting a competitive performance in losing to Aryna Sabalenka.
No.7 seed Yulia Putintseva is playing just her second tournament since shocking erstwhile WTA World No.1 Naomi Osaka at Wimbledon in July. After losing in the second round at SW19, she subsequently went down against Caroline Wozniacki in Toronto a fortnight ago.
Karolina Muchova is set to play her first tournament in a month, having reached the quarterfinals of Wimbledon, where she counted Karolina Pliskova among her victims. She won that particular match 13-11 in the deciding set, narrowly missing out on being one of the first players to play a tiebreak at 12-12 in the major.