Dockerill made his first-team debut for Portsmouth on 1 November 2022, after coming on as a 61st-minute substitute in a 1–1 draw with AFC Wimbledon in the EFL Trophy.[1] On 31 March 2023, he was loaned to Bognor Regis Town.[2] He played six games for Bognor before returning to Pompey in May, signing a professional contract with them on the 12th.[3]
During a pre-season friendly against Gosport Borough in July 2023, Dockerill suffered a serious knee injury, damaging his anterior cruciate ligament as well as tearing his meniscus, an injury that would ultimately rule him out for the duration of the 2023–24 season.[4][5]
On 1 May 2024, Portsmouth said the player would be released in the summer when his contract expired.[6]