[2] During the 2017–18 season he played for the Hibs development team, and he was also loaned to Gala Fairydean Rovers and Queen's Park[3] He scored one of the goals as Hibs won the 2017–18 Scottish Youth Cup final against Aberdeen.
[4] He made his first team debut for Hibernian in July 2018, in a 2018–19 UEFA Europa League qualifier against Faroese club NSI Runavik.
[7] Gullan scored nine goals for Raith during this second spell, which helped to put them top of the 2019–20 Scottish League One table in early January.
[9] Gullan returned to Hibs for the second part of the 2019–20 season, acting as cover for Christian Doidge and Marc McNulty.
[14] On 6 January 2022, Gullan signed for Raith Rovers permanently on a two-and-a-half-year deal for an undisclosed fee.