Watson signed for Third Division South club Brentford in May 1932, joining former Middlesbrough teammates Jack Holliday and Billy Scott at Griffin Park. He led the club to promotion to the Second Division as captain in the 1932–33 season and to the First Division for the first time in the club's history in 1935. After the signing of Dai Richards, Watson lost his place in the team and managed just 13 appearances in the First Division during the 1935–36 season (in which Brentford secured their highest-ever league placing of fifth). He departed the club at the end of the campaign, having made 109 appearances and scored one goal during his four years with the club.
