The son of former professional rugby league footballer Shane Walker,[3] Walker played his junior rugby league for De La Salle Caringbah.

[5] In May 2016, he admitted to using recreational drugs and was banned from playing by the Sharks for 12 weeks.

[7] Walker was selected to represent Italy at the 2017 World Cup qualifying tournament in late 2016.

[8] In 2017, Walker played for the Sharks' feeder team, the Newtown Jets, in the New South Wales Cup.

[10] In November 2017, Walker signed a one-year contract with the Penrith Panthers for 2018.