 He made his first-team debut for the club on 18 September 2012 against Brighton & Hove Albion, coming on as 73rd-minute substitute for Fernando Forestieri.He later made his first start, lasting the full 90 minutes in Watford's 2–2 draw with Bristol City on 23 September.On 17 November, Chalobah scored his first goal for Watford in a 2–1 win over Wolverhampton Wanderers.