 The team also won the Uhrencup that year and Muhmenthaler scored the first goal in the final, as they beat FC Basel 3–1.In the summer of 1972, Muhmenthaler transferred to BSC Young Boys and he played there as Striker for three years.With the Young Boys, Muhmenthaler won the Uhrencup 1973 and he scored a goal in the semifinal against his previous club Grenchen.