Küttel played his youth football for local club FC Emmenbrücke and advanced to their first team in 1971.
Luzern finished level on points, joint second with Chênois, but missed out on promotion losing the play-off match after extra time.
In the semifinal against Lausanne-Sport Seppi Küttel scored the only goal of the match in the 120th minute and so shot the Young Boys into the cup final.
[3] In the high-scoring league match on 14 May 1977 in the Letzigrund against Zürich Küttel scored a hat-trick within 17 minutes and four goals in total as Young Boys won 6–3.
[4] In the 1978–79 season the Young Boys again reached the cup final, which was drawn 1–1 with Servette, but in the replay they were defeated 2–3.
[6] Erni Maissen and Detlev Lauscher led the team's top-scorers list after the qualifying phase, both with 13 league goals.