2013 and 2018 runner-up Kirsten Flipkens leads No.4 seed Lesia Tsurenko 3-1, having defeated the Ukrainian 6-2, 6-2 in Miami qualifying in 2011, 7-5, 3-6, 6-3 in the second round of Memphis in 2013 and 6-2, 6-3 in the first round of New Haven in 2017. Tsurenko won their only encounter outside the USA, taking their 2015 Istanbul semifinal 6-4, 6-2 en route to her maiden title.
Wildcard Destanee Aiava's upset of No.2 seed Aryna Sabalenka was the 19-year-old's third WTA main draw win; her first two both came at home in Brisbane, where she defeated Bethanie Mattek-Sands in 2017 and Kristina Mladenovic in 2018. The latter was Aiava's career-best win before yesterday; at World No.214, she is the second-lowest ranked player to score a Top 10 victory in 2019 following compatriot Kimberly Birrell's upset of Daria Kasatkina in Brisbane.
Qualifier Elena Rybakina is playing her first professional tournament on grass this week. The Kazakh's only previous experience on the surface was at junior level, where she competed in the Wimbledon girls' event twice - losing in the first round both times, to Claire Liu in 2016 and Ellie Douglas in 2017.
2017 runner-up Natalia Vikhlyantseva faces lucky loser and erstwhile junior rival Anna Kalinskaya in the final first-round match. The Russian compatriots have faced each other twice at pro level, with Vikhlyantseva winning both times - 6-1, 6-3 in the final of the Plzen ITF W25 in 2016, and 6-1, 6-2 in Linz qualifying last year. However, Kalinskaya scored a 6-2, 6-1 win in their only junior meeting in the third round of the Beaulieu-sur-Mer Grade 1 event in 2014.
Greet Minnen maintained a 100% record in three WTA main draw openers to date with her first-round defeat of Mona Barthel - her sixth career Top 100 win, all of which have come this year. The 21-year-old Belgian made the Hobart quarterfinals in January and the second round of Stuttgart in April, both also after coming through qualifying, and has raised her ranking from World No.316 at the end of 2018 to her current career high of World No.139.
ORDER OF PLAY (all courts start 11am)
After 1 ATP match, not before 1pm
Lesia TSURENKO (UKR)  vs Kirsten FLIPKENS (BEL)
Natalia VIKHLYANTSEVA (RUS) vs [LL] Anna KALINSKAYA (RUS)
After 1 ATP match
[Q] Elena RYBAKINA (KAZ) vs Alison VAN UYTVANCK (BEL) 
Christina MCHALE (USA) / Alison RISKE (USA) vs Kiki BERTENS (NED) / Demi SCHUURS (NED) 
Margarita GASPARYAN (RUS) vs [Q] Greet MINNEN (BEL)
Not before 12.30pm
Ekaterina ALEXANDROVA (RUS) / Galina VOSKOBOEVA (KAZ) vs Mona BARTHEL (GER) / Andreea MITU (ROU)
Veronika KUDERMETOVA (RUS) vs [WC] Destanee AIAVA (AUS)
Lesia TSURENKO (UKR) / WANG Yafan (CHN) vs Kristyna PLISKOVA (CZE) / Barbora STEFKOVA (CZE)