Qualifier Misaki Doi defeated No.1 seed Kiki Bertens 6-3, 6-0 in their only previous completed match in Sydney qualifying in 2013. However, Bertens scored a win via retirement in the 2017 Nurnberg semifinals - a result that paved the way for the Dutchwoman to win her third career title, but which began a two-year-drought without reaching the last four of another WTA tournament for Doi until her runner-up finish in Hiroshima last month. The Japanese player will be bidding for her first Top 10 win in her 17th match against opponents in that echelon.
Lucky loser Coco Gauff will bid for her maiden WTA quarterfinal against Kateryna Kozlova, who is seeking her third of the year following Budapest and Nanchang. A win for Gauff would make the American the first 15-year-old in the last eight of a WTA tournament since Zarina Diyas at Prague 2009, and the youngest WTA quarterfinalist since Sesil Karatantcheva at Gold Coast 2005.
No.8 seed and last year's finalist Ekaterina Alexandrova will face Kristyna Pliskova for the second time in the past month, having defeated the Czech 3-6, 6-3, 6-4 in their sole prior encounter in the second round of Seoul three weeks ago.
An all-German second-round derby finds No.5 seed and 2012 runner-up Julia Goerges reprising her first-round encounter with Andrea Petkovic last year. Petkovic saved one match point to win that clash 1-6, 7-5, 6-4 and take a 3-2 lead in the Fed Cup teammates' head-to-head, which stretches back to Goerges' win in Sydney qualifying in 2008.
Former World No.45 Anna-Lena Friedsam is bidding to reach her third WTA quarterfinal of the season following Nurnberg and Palermo. The German was ranked as low as World No.558 last December, but is now on an eight-match winning streak after winning the Roehampton ITF W25 title three weeks ago, and scored the first Top 10 victory of her career over No.2 seed Belinda Bencic yesterday.
Barbara Haas is competing in her fifth Linz main draw, with all appearances coming via wildcard. The Austrian is yet to win a match, though has won a set on two previous occasions - against Barbora Strycova in 2015 and Carina Witthoeft in 2017.
ORDER OF PLAY (all courts start 12 noon)
[Q] Tamara KORPATSCH (GER) vs Jelena OSTAPENKO (LAT)
Kateryna KOZLOVA (UKR) vs [LL] Coco GAUFF (USA)
Not before 4pm
 Anastasia PAVLYUCHENKOVA (RUS) vs [WC] Barbara HAAS (AUT)
Not before 6.30pm
[1/WC] Kiki BERTENS (NED) vs [Q] Misaki DOI (JPN)
Andrea PETKOVIC (GER) vs  Julia GOERGES (GER)
 Ekaterina ALEXANDROVA (RUS) vs Kristyna PLISKOVA (CZE)
Viktoria KUZMOVA (SVK) / Yana SIZIKOVA (RUS) vs Dalila JAKUPOVIC (SLO) / Sabrina SANTAMARIA (USA)
Elena RYBAKINA (KAZ) vs [Q] Anna-Lena FRIEDSAM (GER)
Kaitlyn CHRISTIAN (USA) / Alexa GUARACHI (CHI) vs [WC] Coco GAUFF (USA) / Catherine MCNALLY (USA)
 Barbora KREJCIKOVA (CZE) / Katerina SINIAKOVA (CZE) vs Anna-Lena FRIEDSAM (GER) / Varvara LEPCHENKO (USA)