Gilpin followed two cousins and three uncles in being capped for Ireland, with three appearances during the 1962 Five Nations. His debut, against England at Twickenham, was as a fly-half beside another new cap in 17-year old John Quirke, to form Ireland's youngest ever halfback combination at a combined age of 38. England had a convincing win and Gilpin was discarded from the team, only to be recalled when Tom Kiernan got injured, playing his next two matches at fullback.[2] He was an Ireland reserve the following year as a wing three-quarter.[3]
In 1965, Gilpin found employment in London and earned Middlesex representative honours playing for Harlequins.[4]