He spent the entire 2004 season playing with Subiaco and was a part of their premiership team.Impressive WAFL form continued into 2005 and he was selected by Fremantle to make his AFL debut at the MCG against Melbourne in Round 6.

[3] He played 124 consecutive games from his debut until he was a late withdrawal due to stomach cramps before the Round 17, 2010 match against the Western Bulldogs.

[4] 2010 was his best season to date, and he was recognised by being named in the 40-man squad for the 2010 All-Australian team[5] and also won the Doig Medal as Fremantle's best player for the year.

[6] At the end of the 2010 season, there was much speculation that Mundy would not renew his contract with Fremantle and would instead either return to play in Melbourne, or be recruited by the new Gold Coast Football Club.

In the final minutes of the game, a Richmond kick out after a Fremantle behind was marked by Garrick Ibbotson who passed to Mundy approximately 45 metres out from goal.

He would repeat a very similar play again against Richmond at the MCG in 2017, when he marked the ball 25m out from goal with 11 seconds remaining in the game.

[13] In early 2021, Mundy's longevity became the subject of discussion, as he was widely considered to be in career-best form despite his advanced age for an Australian rules footballer.