Biddle was educated at Saint Ignatius' College, Riverview When part of the Parramatta-Melita Eagles, he was awarded the chance to trial with Manchester United.

Biddle later joined Blacktown City Demons at the age of 17, and was part of the 2006 squad that won the Johnny Warren Cup and the 2007 New South Wales Premier League.

[1] Biddle made his debut for Sydney FC against the Central Coast Mariners in the opening game of the season on 24 August 2007; but was given few opportunities under Culina.

[3] In his debut season (2007/08) with the club, Biddle started two games, appeared as a substitute on ten more occasions, featured in other trial and exhibition matches, as well as the inaugural Pan-Pacific Championships in Hawaii and won the Sydney FC Young Player of the Year award.

He signed with Central Coast Mariners Academy in 2013 and after a string of injuries and surgeries he took time off from football, focusing on establishing his landscaping company in Noosa, QLD with his partner Hannah Erken.