Reigning Australian Open and US Open champion Naomi Osaka will be looking for her first win against Yulia Putintseva. Putintseva won their only previous encounter, at Hobart last year, in straight sets.
Read more: Osaka outguns Sakkari in Birmingham opener
Roland Garros champion Ashleigh Barty will be facing Jennifer Brady for the second time. In their only prior meeting, Barty beat Brady in straight sets at the BNP Paribas Open in Indian Wells earlier this year.
For the first time in its history, the Nature Valley Classic featured the players ranked World No.1, No.2 and No.3: Naomi Osaka, Ashleigh Barty, and Karolina Pliskova. Pliskova fell to her twin sister Kristyna in the second round on Wednesday.
Venus Williams and Wang Qiang have met three times previously — all at Grand Slam events. Williams defeated the Chinese No.1 at Roland Garros and Wimbledon in 2017, but Wang claimed a victory over Williams in their most recent clash, in the first round of Roland Garros in 2018.
Julia Goerges and Evgeniya Rodina have split their four prior matches against each other. Rodina won two of their three tilts between 2009 and 2011, but Goerges won their most recent meeting, at Beijing in 2016. This will be their first matchup on grass.