|Position||Second Row, Front Row|
|DOB||15th Apr 1980|
|Origin||Auckland, New Zealand|
|Junior Club||Toronto Scorpions|
|Debut||2000: Round 13 vs Penrith|
|Other Clubs||Roosters, North Queensland, Newcastle, Manly|
|Rep||NSW(13), Aus(24), Tonga(3)|
Willie Mason joined Canterbury in 1998 as a prop forward and was regular member of the Flegg team.
In 1999, Willie was again a regular member of the Flegg team and played in the Preliminary Final against Parramatta, only to suffer a leg fracture and miss the Grand Final win.
In 2000, Willie started the season in 1st Division and received the opportunity to play in the NRL against Penrith when Darren Britt was injured. He impressed early and became a regular member of the NRL team for the rest of the season.
In 2001, Willie became a regular member of the NRL team and played in the Semi Final loss against Cronulla.
In season 2002, Willie was selected to play for Australia and since then has racked up a total of 21 Tests for Australia along with seven games for NSW from 2003 to 2006. Willie was a member of the 2003 Kangaroo tour and toured with the Tri-Nations squad in 2004 and 2005. Willie played in the 2006 Tri-Nations series and became the Bulldogs most capped Test player.
In 2003, Willie was a regular member of the team and played in the Preliminary Final loss against the Roosters.
In 2004, Willie played in the Premiership winning team against the Roosters and won the Clive Churchill Medal in the 16-13 thriller at Telstra Stadium. The medal meant the world to the 195cm giant.
In 2004, Willie was nominated for the Berries to Bulldogs 70 Year Team of Champions.
In 2005, Willie's season was over before it started after suffering a fractured ankle during Australia's 36-24 win over USA in an international rugby league match at Philadelphia's Franklin Field in December 2004. Mason was out of action for most of the season and did not play in the NRL until Round 18 against the Warriors.
In 2006, Willie returned to become a regular member of the NRL team where he managed to play 20 club matches (1157 minutes), all three Origin games for NSW - in which he was named Man of the Match in the opening game and three Tests for Australia in the Tri-Nations series. Many believe if it wasn't for his suspension following an incident in Round 24 against Brisbane, he could have well been named the Dally M Player of the Year.
In 2007, Willie played just 15 games due to a wrist injury. He played in all three games for New South Wales and wore the Australian jersey twice, in the ANZAC Test and Centenary Test.
Despite being contracted until the end of season 2009, on November 15 of 2007, Willie Mason was granted a release from his contract to join the Sydney Roosters.
On 1st August 2015, Willie was named in the team of the decade as part of the clubs 80th Year celebrations.
In 2018, Willie was awarded Life Membership of the Football Club.