Basel continued their dominance of Swiss soccer by winning their fourth successive league title, and a seventh in 10 seasons, with a 1-0 home victory over St Gallen in the final game on Saturday.
Argentine forward Raul Bobadilla was on target in the 22nd minute, his first goal since joining the club from Young Boys Berne in the mid-season break.
Basel, who boast an average attendance of more than 28,000, finished three points clear of record title winners Grasshoppers who beat Lausanne Sport 4-1 just hours after coach Uli Forte confirmed he was moving to Young Boys next season.
Champions Basel, who replaced coach Heiko Vogel with Murat Yakin in October, played 62 matches in a marathon season which began in mid-July and included a 20-game European campaign which took them to the Europa League semi-finals.
St Gallen's Ezequiel Scarione finished as the league's top scorer with 21 goals while Sion sacked five coaches including former Italy midfielder Gennaro Gattuso on their way to finishing sixth in the 10-team table.
Basel and Grasshoppers go into the third qualifying round of next season's Champions League.