[2] On 9 April 2016, Colkett was named upon the first-team substitute bench along with fellow academy players Ola Aina and Kasey Palmer, in Chelsea's 1–0 away defeat to Swansea City.

[10] Three days later, Colkett made his Swindon Town debut in their 2–1 victory over Bolton Wanderers, assisting Yaser Kasim's late winner in the 89th minute, before being replaced by Sean Murray with seconds remaining.

[16] He started in the season-opening 1–0 home loss to Bradford City but made only five more appearances – all in cups – before Shrewsbury ended his loan prematurely on New Year's Eve.

[22] He made his debut with a substitute appearance in Crewe's second game of the 2022–23 season, a 3–0 win over Harrogate Town at Gresty Road on 6 August 2022.

[23] He made his first Crewe start on 9 August 2022, playing in an EFL League Cup first round defeat at Grimsby Town,[24] but suffered a severe hamstring injury sidelining him for at least three months.

[25] He made a return in November 2022 and on 1 January 2023 scored his first (only) Crewe goal, the winner in a 1–0 victory over Tranmere Rovers at Gresty Road[26] but limped off after he suffered another hamstring injury ruling him out for several weeks.