Gilvarry first appeared for Mayo in 1945. He won the first of four consecutive Connacht SFC titles in 1948, however, Mayo were later beaten by Cavan in the 1948 All-Ireland final. He claimed his first silverware the following year after victory in the National League. Gilvarry was one of the key forwards when Mayo claimed back-to-back All-Ireland SFC titles after defeats of Louth in 1950 and Meath in 1951. His inter-county performances also earned inclusion on the Connacht team, with Gilvarry winning a Railway Cup medal in 1951.
