Buchan was a regular at Arsenal for three seasons. He captained Arsenal to their first ever Cup final in 1927, which they lost 1–0 to Cardiff City. Buchan finally retired at the end of 1927–28, having scored 16 league goals that season despite being 36 years of age. In all he scored 56 goals in 120 matches for Arsenal; his count of 257 goals in the League (which would have been more had the First World War not intervened) makes him the Football League's 33rd-highest goalscorer of all time.