At club level he played for the Huddersfield Giants, Hull Kingston Rovers, St Helens, Wakefield Trinity and the Salford Red Devils in the Super League, and on loan from Huddersfield at the Barrow Raiders and the Swinton Lions in the Championship.

[7] Walker played 107 times for Hull KR until he rejected a reduced contract when the club was relegated after losing the Million Pound Game to Salford.

[citation needed] After departing Hull KR, Walker signed for St Helens for the 2017 season.

After an unsuccessful start to the season at St Helens, Walker signed for Wakefield on a 2½-year deal[8] but only played 7 times before being dismissed when he tested positive for cocaine.

On 27 January 2016, Walker was charged with two offences of attempting to engage in sexual activity with a child, with a court appearance due later in February of that year.