A New South Wales State of Origin representative, he played for the Newcastle Knights in the National Rugby League as a winger.

McManus was born in Banff, Aberdeenshire, Scotland and moved to Darwin, Northern Territory, Australia at the age of nine after his father died and his mother married an Australian man.

[5] McManus played for the Knights in the Jersey Flegg Cup before graduating to their NSWRL Premier League team.

[8] For the third and deciding game of the 2013 State of Origin series McManus was selected as wing for New South Wales, and scored a try in the Blues' loss.

After suffering a concussion in Round 20 of the 2015 season, McManus was sidelined for the rest of the year and it was speculated that he would be forced to retire.