Emerson made his Premier League debut on 4 March 2018 as a second-half substitute in a 1–0 defeat at Manchester City. His first Premier League start came away to Burnley on 19 April. Emerson set up Victor Moses for the winning goal as Chelsea claimed a 2–1 victory. Chelsea went on to win the 2017–18 FA Cup but Emerson was injured and missed the final.