In preparation for the new campaign, manager Billy McNeill strengthened his squad by signing Arsenal winger Martin Hayes, former Celtic hero Charlie Nicholas, and rising star John Collins.

In the 1990–91 Scottish League Cup, Celtic reached the final after overcoming lower-league opposition in the early rounds and defeating Dundee United in the semi-final.

Celtic, aiming to reach their fourth consecutive final, gained a measure of hope with a famous St. Patrick's Day victory over rivals Rangers.

Following another trophyless campaign and after spending over £2 million on new signings, the board of directors dismissed Billy McNeill, ending his long-standing association with the club.

Celtic prepared for the 1990–91 season with a tour of Germany and Holland before travelling to Ireland to play in the Bohemian centenary celebration match.