 He was also a member of the Roosters side that won the 2003 World Club Challenge, and appeared in the 2003 NRL Grand Final loss to the Penrith Panthers.Cusack played for the Roosters from the interchange bench in their 2004 NRL grand final loss to cross-Sydney rivals, Canterbury-Bankstown.In 2005, Cusack joined the South Sydney Rabbitohs, that year winning the George Piggins Medal as the club's best and fairest player for the season.