Play starts at 2pm
CoCo Vandeweghe (USA)  v Catherine Bellis (USA) 
After suitable rest. (Possible court change)
Abigail Spears (USA) / Coco Vandeweghe (USA)  v Anastasia Pavlyuchenkova (RUS) / Olga Savchuk (UKR)
Not before 7pm
Garbiñe Muguruza (ESP)  v Madison Keys (USA) 
Alizé Cornet (FRA) / Alicja Rosolska (POL) v Kayla Day (USA) / Caroline Dolehide (USA)
Madison Keys is yet to be beaten by Garbiñe Muguruza, triumphing over the Spaniard in Cincinnati in 2012 and again in Rome, on clay, last year.
Compatriots CoCo Vandeweghe and Catherine Bellis meet for the first time.
The Stanford tournament has been won by a home player just three times since Lindsay Davenport's success in 2004. Serena Williams' 2011 victory preceded further wins in 2012 and 2014 for the same player.
The last American to reach the final was Venus Williams, who lost to Johanna Konta in three sets last summer.
CoCo Vandeweghe seeks to reach her second Stanford final, having previously reached the showpiece match in 2012 - when she was beaten by Serena Williams.
Garbiñe Muguruza tasted success in the doubles in Stanford three years ago, partnering Carla Suárez Navarro to victory over Paula Kania and Katerina Siniakova in the 2014 final.