Play starts at 11am
Catherine Bellis (USA)  v Veronica Cepede Royg (PAR)
Not Before 1pm
Kateryna Bondarenko (UKR) v Petra Kvitova (CZE) 
Alison Riske (USA) v Anastasia Pavlyuchenkova (RUS) 
Not Before 7pm
CoCo Vandeweghe (USA)  v Nicole Gibbs (USA)
Jennifer Brady (USA) / Madison Keys (USA) v Alizé Cornet (FRA) / Alicja Rosolska (POL)
CoCo Vandeweghe's only previous meeting with compatriot Nicole Gibbs came at the same stage of the same event last year - the 25-year-old prevailing in three sets before losing to Alison Riske in the last eight.
Alison Riske holds a 3-1 lead over Anastasia Pavlyuchenkova - her only loss coming in Moscow three years ago.
Veronica Cepede Royg seeks to maintain her winning record over Catherine Bellis - having won their only previous match, over two sets in French Open qualifying in 2015.
Petra Kvitova and Kateryna Bondarenko meet for the fifth time but the first since the 2012 Olympic Games. Both have won twice against the other, Bondarenko's two wins coming on hard courts.