A Melbourne boy, Simpson played junior football for Eltham and the Northern Knights before being recruited to North Melbourne in the 1993 National Draft.

Debuting late in 1995, Simpson had just 27 games to his name when he featured in North Melbourne’s 1996 Premiership win. He added a second Premiership in 1999, where he played a key midfield role and amassed 27 disposals.

One of the most consistent ball winning midfielders in the competition, Simpson regularly finished in the top five in club best and fairest awards. He won his sole Syd Barker Medal in 2002, the same year he earned All-Australian selection.

Simpson was appointed Club Captain in 2004, leading the side back into finals the following year. He held this position for five years before stepping down at the back end of his career.

In 2009 Simpson celebrated his 300th game, becoming the 3rd North Melbourne player to do so. He retired at the end of the 2009 season with 306 games to his name, missing only 7 games across his career as a regular player.

After retiring, Simpson transitioned into coaching and took up a role with Hawthorn as an assistant coach from 2010 to 2013, playing a leading role in Hawthorn’s 2013 Premiership.

Simpson was appointed Senior Coach of the West Coast Eagles at the end of 2013 taking over from long standing coach John Worsfold. In 2018, Simpson coached the Eagles to their second Grand Final appearance in 4 seasons which resulted in the Clubs fourth Premiership victory.

The game was arguably one of the best Grand Finals in recent decades going down to the wire with the Eagles ultimately snatching victory from Collingwood in the closing minutes.