CENTRE COURT -- 1:00 pm start
Anna BLINKOVA (RUS) / Oksana KALASHNIKOVA (GEO) vs. [WC] Anastasia PAVLYUCHENKOVA (RUS) / Lucie SAFAROVA (CZE)
Not Before 3:30 pm
 Petra KVITOVA (CZE) vs.  Kiki BERTENS (NED)
Not Before 6:30 pm
[WC] Mona BARTHEL (GER) / Anna-Lena FRIEDSAM (GER) vs Gabriela DABROWSKI (CAN) / Jelena OSTAPENKO (LAT)
Naomi Osaka withdrew injured from her semifinal against Anett Kontaveit, giving the Estonian a walkover.
Petra Kvitova and Kiki Bertens have split their four previous meetings. Kvitova won the first two clashes, at 2015 Wimbledon and the final of the 2018 Mutua Madrid Open. Bertens won their most recent two matches, both last year after Madrid, at Montreal and Cincinnati. The 2018 Madrid final is their only previous meeting on clay.
18 different players have won the 18 WTA singles titles contested so far this year. Kvitova (Sydney) and Bertens (St. Petersburg) are all attempting to become the first player to win two titles in 2019.
By reaching the quarterfinals, Osaka is guaranteed to exit Stuttgart retaining the World No.1 ranking. She has held the No.1 ranking for 13 weeks thus far, having attained it for the first time after defeating Kvitova in the Australian Open final.
Bertens stands at 187 aces for the year, which has her second for the season in total aces behind Karolina Pliskova's 192, meaning Bertens can pass Pliskova for the lead with six more aces this week. Kvitova is third with 133 aces in 2019.