He played for the South Sydney Rabbitohs, Melbourne Storm, Gold Coast Titans and Parramatta Eels in the National Rugby League.

Champion made his first-grade debut in round 18 of the 2005 NRL season in a 24–14 win over the Cronulla-Sutherland Sharks at the old Sydney Football Stadium.

On 8 January 2013 the South Sydney Rabbitohs announced that Champion would be returning home to Redfern on a two-year deal covering the 2013–2014 seasons.

Titans coach John Cartwright was very supportive of Champion's decision to return to NSW saying "I think most people agree that you play your best football where you are happy and after sitting down and talking with Beau about this opportunity to go back to Souths, we fully understand his reasons why.

On 19 August 2015 Champion announced his retirement from rugby league after failing to recover from an Anterior cruciate ligament injury sustained during the round 2 match against the Canterbury-Bankstown Bulldogs.