He represented Grasshoppers during three successful seasons, also setting a record for the club as the youngest player to make his debut in the Swiss Challenge League.

Sforza was signed at the same time as German superstar Jürgen Klinsmann, compared to the homely smalltown club Kaiserslautern, Bayern was a team with many stars.

Conflicts between Klinsmann and team captain Lothar Matthäus poisoned the atmosphere and many scandals underlined why Bayern is nicknamed FC Hollywood.

[2] Although Hodgson had initially purchased him as to function as a playmaker, to solve Inter's lack of creativity in midfield, Sforza had problems performing consistently, and he spent a lot of time on the bench, although he was able to reach the UEFA Cup final with the club, and also managed a third-place finish in the league.

[3] During his time with Inter, Sforza became known for his inconsistency in Serie A, and he is famously remembered in Italy for being referenced in the Italian film Tre Uomini e una Gamba, by Italian comedic trio Aldo, Giovanni e Giacomo; in the film, Aldo states that he had to purchase Sforza's number 21 Inter jersey as Ronaldo's was out of stock.

In time for the 1997–98 season, Sforza moved back to Kaiserslautern where he immediately made an impression, experiencing a more successful stint with the club and finally demonstrating strong and consistent performances, which justified his reputation as one of the leading Swiss players of his generation.

FC Bayern had many star players competing for places, and the team won both the 2000–01 Bundesliga and 2000–01 UEFA Champions League titles that season.

The aging and now somewhat injury-prone Sforza helped FCK avoid relegation, however, in October 2005, he had a public falling-out with the club and was blackballed.

[2] Sforza was selected to play for Switzerland at the 1994 FIFA World Cup by national manager Roy Hodgson, putting on a notable performance, and reaching the round of 16.

[11] Sforza's first match was on 17 September in the 2020–21 UEFA Europa League second qualifying round against Croatian team Osijek which ended with a 2–1 victory.

[12] On 6 April 2021 the club announced that, due to the lack of sporting success, FC Basel 1893 were separating themselves from head coach Ciriaco Sforza with immediate effect.