Play starts at 10am
Caroline Dolehide (USA) v Naomi Osaka (JPN)
Not before 11.30am
Alison Riske (USA) v Magda Linette (POL)
CoCo Vandeweghe (USA)  v Ajla Tomljanovic (CRO)
Veronica Cepede Royg (PAR) v Kristie Ahn (USA)
Not before 7pm
Catherine Bellis (USA)  v Alizé Cornet (FRA)
Francesca Schiavone (ITA) v Kateryna Bondarenko (UKR)
Play starts at 11.30am
Anastasia Pavlyuchenkova (RUS) / Olga Savchuk (UKR) v Melissa Lord (USA) / Carol Zhao (CAN)
Not before 1pm
Chia-Jung Chuang (TPE) / Miyu Kato (JPN)  v Kayla Day (USA) / Caroline Dolehide (USA)
Not before 2.30pm
Raquel Atawo (USA) / Hao-Ching Chan (TPE)  v Jennifer Brady (USA) / Madison Keys (USA)
Catherine Bellis went out in the opening round at Stanford in 2015, losing to Misaki Doi. Her best showing at the tournament remains last year's run to the quarterfinals, where she was beaten by Venus Williams.
Naomi Osaka has made it to the last 16 in Stanford on one previous occasion - losing to Andrea Petkovic three years ago.
Alison Riske seeks an opening-round victory at Stanford for the third year in succession, having beaten Tatjana Maria at the same stage two years ago and Varvara Lepchenko last year.
CoCo Vandeweghe has begun her last four Stanford campaigns (2012, 2013, 2014 and 2016, including qualifiers) against a fellow American. The last time she opened against someone from outside her country was back in 2011, when she was beaten by Canadian Rebecca Marino in the opening round.
Since making the semifinals in 2003, Francesca Schiavone has won three of her four opening-round matches at Stanford.
Alison Riske won her only previous meeting with Magda Linette, in straight sets in Tianjin last year.
Francesca Schiavone is yet to lose against Kateryna Bondarenko, prevailing at The Fed Cup in 2010 and 2012 having already beaten the Ukraninan in 2009.