Both courts start at 10.30am
Anett Kontaveit (EST)  v Martina Trevisan (ITA)
Caroline Garcia (FRA)  v Elitsa Kostova (BUL)
Tamara Korpatsch (GER) v Jil Teichmann (SUI)
Not before 3.30pm
Antonia Lottner (GER) v Viktorija Golubic (SUI) 
Not Before 5.30 pm
Amra Sadikovic (SUI) v Patty Schnyder (SUI)
Evgeniya Rodina (RUS)  v Sara Sorribes Tormo (ESP)
Basak Eraydin (TUR) v Barbara Haas (AUT)
Irina Khromacheva (RUS) v Tereza Martincova (CZE)
Johanna Larsson (SWE)  v Viktoriya Tomova (BUL)
Viktorija Golubic begins the defence of a title she won last year, beating Kiki Bertens in three sets in the final.
Golubic became only the second home player to triumph at the event, following Manuela Maleeva-Fragniere's 1991 success.
Last year's tournament marked the event's return to Gstaad for the first time since 1978. The tournament had been held in Lugano, Geneva and Lucerne in the intervening years.
Anett Kontveit reached the second round in Gstaad last year, losing to Rebeka Masarova. The Estonian has reached three WTA finals in recent weeks, losing in Biel before victories in 's-Hertogenbosch and Andrezieux-boutheon.