League of Ireland Shield

The League of Ireland Shield (Irish: Sciath Sraithe na hÉireann) is a defunct Irish football tournament which was introduced when the League of Ireland started in 1921 and ran uninterrupted until 1972. It was played before the league season began and was seen as the 3rd most important trophy in Irish football, after the league and FAI Cup. The winners of the Shield gained entry to the following seasons Inter-Cities Fairs Cup until 1971-1972.

It was played in a variety of formats; from complete round robin series to group stages followed by knock out games to complete knock out tournaments. It was replaced by the League of Ireland Cup in 1973.

The LOI Shield should not be confused with the League of Ireland First Division Shield, a competition that ran in the 1980s and 1990s and, as the name suggests, was confined to First Division clubs.

...
Wikipedia