No.4 seed Belinda Bencic leads the head-to-head against Anastasia Pavlyuchenkova 4-1 - although the Russian's one win was also their sole previous outdoor hardcourt meeting, in the second round of Washington 2015, which Pavlyuchenkova won 6-2, 6-4 en route to the final. Three of Bencic's four victories have come in three sets: 6-3, 3-6, 6-3 in the first round of Rome 2014, 6-7(4), 6-4, 6-2 in the 2016 St. Petersburg quarterfinals and 3-6, 6-1, 6-1 in their most recent encounter in October's Moscow final. The Swiss player's only straight-sets triumph in the series came in the first round of Wimbledon last year, 6-2, 6-3. Bencic is also bidding to win her first ever match as a WTA defending champion. Previously, the World No.4 lost her second-round opener at Eastbourne 2016 to Elena Vesnina, and was unable to defend her Rogers Cup title in the same year due to a wrist injury.
No.3 seed and two-time champion Elina Svitolina defeated Jennifer Brady 6-2, 6-4 in their only previous meeting, in the first round of Montréal 2016. The Ukrainian, who won the Dubai title in 2017 and 2018 and reached the semifinals in 2016 and 2019, is one of three former winners in this year's draw alongside Bencic and 2015 champion Simona Halep.
Two of the most in-form players of 2020 clash for the first time as Australian Open champion Sofia Kenin, in her first WTA Tour match since lifting her maiden major trophy in Melbourne, takes on Elena Rybakina, fresh off her third final of the season in St. Petersburg.
No.7 seed Aryna Sabalenka and Maria Sakkari have split two previous matches, both also on outdoor hard courts in the past seven months. Sakkari came from a set and 1-4 down to take the first encounter 6-7(4), 6-4, 6-4 in the third round of Cincinnati, but three months later Sabalenka avenged the defeat 6-3, 6-4 in the Zhuhai round-robin stage en route to the title.
Lucky loser and 2019 semifinalist Hsieh Su-Wei, who is still looking for her first main draw win of 2020, leads the head-to-head against No.8 seed Petra Martic 2-1. Hsieh took their first match - and her maiden WTA title - when Martic retired trailing 2-6, 7-5, 4-1 in the 2012 Kuala Lumpur final, and their most recent 6-3, 7-6(8) in Wimbledon qualifying in 2015. Martic's sole win in the series came on clay in the second round of Budapest 2012.
Qualifier Veronika Kudermetova leads Dayana Yastremska 2-0, having defeated the Ukrainian 1-6, 6-2, 6-3 in the semifinals of the Telavi ITF 25K on clay in 2016 - and then again at WTA level last October, winning 6-4, 6-0 in the Tianjin quarterfinals.
In an all-qualifier clash, Aliaksandra Sasnovich leads the series against Kristina Mladenovic 4-2, including their last three encounters - and is also 2-0 against the Frenchwoman on outdoor hard courts. Their last four matches have all been three-setters, however: Mladenovic won 3-6, 6-2, 6-2 in the second round of 's-Hertogenbosch 2017 before Sasnovich triumphed 6-2, 2-6, 6-2 in the second round of Moscow 2017, 1-6, 6-3, 7-5 in the first round of Brisbane 2018 and 7-6(6), 6-7(3), 6-2 in the first round of New Haven 2018.
ORDER OF PLAY
CENTRE COURT (starts 2pm)
[3/WC] Elina SVITOLINA (UKR) vs [Q] Jennifer BRADY (USA)
Anastasia PAVLYUCHENKOVA (RUS) vs  Belinda BENCIC (SUI)
Not before 7pm
 Sofia KENIN (USA) vs Elena RYBAKINA (KAZ)
Maria SAKKARI (GRE) vs  Aryna SABALENKA (BLR)
COURT 1 (starts 12 noon)
Karolina MUCHOVA (CZE) vs [Q] Katerina SINIAKOVA (CZE)
[Q] Kristina MLADENOVIC (FRA) vs [Q] Aliaksandra SASNOVICH (BLR)
[Q] Veronika KUDERMETOVA (RUS) vs Dayana YASTREMSKA (UKR)
 Petra MARTIC (CRO) vs [LL] HSIEH Su-Wei (TPE)
[Q] Sorana CIRSTEA (ROU) vs Anett KONTAVEIT (EST)
COURT 2 (starts 2pm)
Desirae KRAWCZYK (USA) / Alison RISKE (USA) vs Kaitlyn CHRISTIAN (USA) / Oksana KALASHNIKOVA (GEO)
Hayley CARTER (USA) / Luisa STEFANI (BRA) vs Lucie HRADECKA (CZE) / Andreja KLEPAC (SLO)
Karolina MUCHOVA (CZE) / Marketa VONDROUSOVA (CZE) vs Jennifer BRADY (USA) / Anastasija SEVASTOVA (LAT)
COURT 3 (starts 2pm)
 Shuko AOYAMA (JPN) / Ena SHIBAHARA (JPN) vs Karolina PLISKOVA (CZE) / Kristyna PLISKOVA (CZE)
HAN Xinyun (CHN) / PENG Shuai (CHN) vs Cornelia LISTER (SWE) / Renata VORACOVA (CZE)
 Barbora KREJCIKOVA (CZE) / ZHENG Saisai (CHN) vs Alexa GUARACHI (CHI) / Alicja ROSOLSKA (POL)
[WC] Caroline GARCIA (FRA) / Sania MIRZA (IND) vs Alla KUDRYAVTSEVA (RUS) / Katarina SREBOTNIK (SLO)