Switzerland beat European champions Portugal 2-0 in their opening World Cup 2018 Group B qualifier on Tuesday.
Breel Embolo and Ahmed Mehmedi scored first-half goals for the hosts, who had Arsenal midfielder Granit Xhaka sent off in stoppage time.
Portugal were missing Cristiano Ronaldo, with the Real Madrid forward injured since July's Euro 2016 final.
Beaten finalists France got their own campaign off to a slow start with a 0-0 Group A draw in Belarus.
Elsewhere in that group, Sweden held the Netherlands to a 1-1 draw with a Wesley Sneijder goal cancelling out a chip from Marcus Berg, while Bulgaria beat Luxembourg 4-3 thanks to an injury-time winner from former Aston Villa winger Aleksandar Tonev.