Three-time defending champion Basel is all but certain to win the Swiss League title after beating Young Boys 1-0 on Wednesday.
A penalty by Fabian Frei was enough to seal the win in a memorable season that saw them reach the UEFA Europa League semi-finals, beating Spurs on the way, where they lost to eventual winners Chelsea.
Basel stands three points clear of Grasshoppers with one round remaining and has a superior goal difference of 16.
Grasshoppers assured its top-two finish by beating third-placed Saint Gallen 2-1 and will join Basel in next season's UEFA Champions League. Both enter the third qualifying round, needing to beat two opponents to reach the lucrative group stage.
Basel can clinch its 16th league title at home to Saint Gallen on Saturday. Grasshoppers is at home to Lausanne.
Lausanne condemned Servette to relegation with a 3-0 win against its local rival.
Servette will be replaced by second-tier champion Aarau.