Play starts at 3:30pm on all courts
[4 / WC] Elina SVITOLINA (UKR) vs Jelena OSTAPENKO (LAT)
 Kiki BERTENS (NED) vs Carla SUAREZ NAVARRO (ESP)
 Simona HALEP (ROU) vs Lesia TSURENKO (UKR)
Not Before 8:00pm
Anett KONTAVEIT (EST) vs  Angelique KERBER (GER)
HSIEH Su-wei (TPE) vs [Q] Karolina MUCHOVA (CZE)
Elise Mertens (BEL) vs [LL] Kristyna Pliskova (CZE)
 Anna-Lena GROENEFELD (GER) / Demi SCHUURS (NED) vs Miyu KATO (JPN) / Makoto NINOMIYA (JPN)
 Nicole MELICHAR (USA) / Kveta PESCHKE (CZE) vs [Alt] Ons JABEUR (TUN) /
Alison RISKE (USA)
[Q] Anna BLINKOVA (RUS) vs Barbora STRYCOVA (CZE)
[LL] Alison RISKE (USA) vs  Julia GOERGES (GER)
Veronika KUDERMETOVA (RUS) / Jelena OSTAPENKO (LAT) vs  HSIEH Su-wei (TPE) / Barbora STRYCOVA (CZE)
Mihaela BUZARNESCU (ROU) / Alicja ROSOLSKA (POL) vs Darija JURAK (CRO) / Maria Jose MARTINEZ SANCHEZ (ESP)
Nadiia KICHENOK (UKR) / Aliaksandra SASNOVICH (BLR) vs Raquel ATAWO (USA) / Katarina SREBOTNIK (SLO)
Lara ARRUABARRENA (ESP) / Kaitlyn CHRISTIAN (USA) vs  Gabriela DABROWSKI (CAN) / XU Yifan (CHN)
The 2014 Qatar Total Open champion and finalist both start their campaigns in the second round on Wednesday: Simona Halep defeated Angelique Kerber in the final five years ago.
Halep has a commanding 5-0 head-to-head lead over her second-round opponent Lesia Tsurenko. They most recently played in the quarterfinals of Cincinnati last year, where Halep won 6-4, 6-1. Tsurenko, however, would go on to make her first Grand Slam quarterfinal at the US Open later that summer.
Kerber has never won a set against her second-round opponent Anett Kontaveit in their two previous meetings, which both came on clay courts. Kerber retired while trailing 6-0, 2-0 during their most recent encounter, at Stuttgart last year.
Carla Suarez Navarro beat Jelena Ostapenko in the 2016 Doha final, and both players are still active in this year's draw. However, they both have challenging second-round matches against Top 5 seeds: Suarez Navarro meets No.5 seed Kiki Bertens, while Ostapenko takes on No.4 seed Elina Svitolina.
Ostapenko has a 2-0 head-to-head lead on Svitolina. The 2017 French Open champion beat the World No.7 in straight sets at Wimbledon in 2017, and followed up by ousting her in two tiebreak sets at Miami last year. Ostapenko would go on to the Miami final before falling to Sloane Stephens.
Karolina Pliskova has withdrawn from singles and doubles due to viral illness. She is replaced in the singles draw by Kristyna Pliskova as lucky loser and in doubles by the team of Jabeur/Riske as alternates.