[4] Walker is a product of the London Broncos academy system and made his first team debut on 13 September 2014.

Before joining London Broncos Academy, Walker played for Brentwood Eels RLFC as a youth player.

[5] Walker played a pivotal role in the Broncos' successful 2018 season, the culmination of which was their 4-2 win over the Toronto Wolfpack in the Million Pound Game to earn promotion to Super League in 2019.

[6] On 3 August 2021 it was reported that he had signed for Featherstone Rovers in the RFL Championship on loan until the end of the 2021 season.

[9] On 15 October 2023, Walker played in the London Broncos upset Championship Grand Final victory over Toulouse Olympique.