Guerin played in the second row of a strong Galwegians side which dominated the late 1950s. A regular Connacht representative, Guerin and Charlie Lydon share the distinction of being the province's first forwards to gain an Ireland cap, when they appeared against Scotland at Lansdowne Road in 1956.[1]
A banker, Guerin remained involved in rugby as an administrator and served as Galwegians president in 1973-74.[2]
Guerin's two sons, Enda and Shane, both played rugby for Connacht.[3]