He was a defender who was drafted with pick 66 in the 1999 AFL Draft from the Perth Football Club. Throughout 2002 he grew and developed as a defender and became an essential part of the Western Bulldogs' defence. In the same year, Hargrave was nominated for the AFL Rising Star award. Hargrave also won the Western Bulldogs' Best First Year Player award in 2002.
In 2003, Hargrave was fined $2,000 and suspended for three weeks by the tribunal after he punched Heath Black during a melee against the St Kilda Saints.
After playing only five games in 2011 due to repeated foot and ankle injuries, it was thought that he would be delisted by the Bulldogs' new coach Brendan McCartney. However, he was retained on the list and in 2012 he played eight of the first nine games and reached his 200 game milestone in round ten.
He retired at the completion of the 2012 AFL season.