Play starts at 11:30am
Elise MERTENS (BEL) v Daria KASATKINA (RUS)
Anastasija SEVASTOVA (LAT)  v Jelena OSTAPENKO (LAT)
[Q] Sara SORRIBES TORMO (ESP) v [WC] Andrea PETKOVIC (GER)
Not before 6:30pm
Lesia TSURENKO (UKR) v [WC] Laura SIEGEMUND
Kiki BERTENS (NED)  v [Q] Anna-Lena FRIEDSAM
Play starts at 2pm
[WC] Anastasia PAVLYUCHENKOVA (RUS) / Lucie SAFAROVA (CZE) v Lyudmyla KICHENOK (UKR) / Nadiia KICHENOK (UKR)
[Q] Greet MINNEN (BEL) v [WC] Dominika CIBULKOVA (SVK)
Not before 6pm
Nicole MELICHAR (USA) / Kveta PESCHKE (CZE)  v Darija JURAK (CRO) / Raluca OLARU (ROU)
Elise Mertens is playing in Stuttgart for the first time.
Daria Kastakina trails 1-0 to the Belgian in their head-to-head record at Tour level, while the Russian has never won a match in Stuttgart in two previous visits.
Latvia’s top two players, No.7 seed Anastasija Sevastova and Jelena Ostapenko, meet for the first time in a Tour-level match.
Sevastova had a strong 13-5 winning record on clay in 2018.
Ostapenko’s last victory over a Top 20 player came in Miami in March 2018. She beat Petra Kvitova and Elina Svitolina that week.
Wildcard Andrea Petkovic is playing Stuttgart for the 11th time. Her previous best was a run to the quarterfinals of 2011, where she was beaten by Caroline Wozniacki.
There are four former champions in the draw, but only Laura Siegemund will play on Tuesday. Karolina Pliskova, Julie Goerges and Angelique Kerber will have to wait to open their campaigns.
Should Kiki Bertens overcome Anna-Lena Friedsam, it would represent her 80th main draw career win on clay.
Only Karolina Pliskova (183) has hit more aces this year than the Dutchwoman’s 158.