Muhmenthaler reached his third Uhrencup Final with his third club in 1977 but was unable to repeat the success, the final ended in a 6–1 defeat against Neuchâtel Xamax. Reaching the final again in the next year, Basel won the 1978 Uhrencup 2–1 against the same finalists.
Muhmenthaler's third Uhrencup Final appearance with his third team in 1977 ended in a disappointing loss to Neuchâtel Xamax. However, he was able to redeem himself the following year when Basel won the 1978 Uhrencup by defeating the same finalists 2–1.