 He scored two goal in 23 appearances across the 2017 season, helping the "Rebel Army" to win both the Premier Division title and the President of Ireland's Cup, though he was an unused substitute in the final at Turners Cross.On 4 November, he entered the final of the FAI Cup at the Aviva Stadium as a substitute in extra-time, and went on to score the equalising goal of a 1–1 draw; Cork went on to win the trophy on penalties.On 2 January 2018, Campion joined NIFL Premiership club Linfield on loan for the rest of the 2017–18 season; manager David Healy said "he's a player we know well and have seen play live several times".