 He moved to London to share a medical practice in Clapton with his brother-in-law, John L. Scott, who was also the Arsenal team doctor.Paterson was persuaded to sign for Arsenal as an amateur and made his debut on the left wing against Derby County on 30 October 1920.Paterson became a regular fixture in the Arsenal side that season, and even played for the English Football League XI against the Scottish League XI (he had been ineligible to represent Scotland due to his birthplace under the rules of the time.