Forbes was played for Bay of Plenty in the Mitre 10 Cup from 2018 to 2020.[2] He credits ex-Glasgow Warrior Hugh Blake, who was a teammate at Bay of Plenty, for the opportunity to move to Glasgow. "[Hugh] found out I had Scottish grandparents. He set the groundwork for me and went to find out if anyone would be keen to take me on. The three-month trial came up with Glasgow and things went better than I thought. It was always on my mind to play in Scotland during my career, I just never thought the opportunity would come this early."[3] He joined Glasgow Warriors in February 2021.[4] He is Scottish qualified.
He started for the Warriors in their match against Leinster on 28 February 2021, becoming Glasgow Warrior No. 323.[5] He won Warrior of the Month for April 2021. He made 38 caps for the club, scoring 11 tries. He was released by the Warriors in the summer of 2023.
International career
In June 2021 Forbes was called up to the Scotland squad for the Summer internationals.[6]