 Ritson began playing rugby league at an early age for the Miranda Magpies in the Sutherland Shire and was quickly earmarked as a star player for his advanced skills at such a young age along with his size.He later moved on to rival club the Engadine Dragons before being signed to the Cronulla-Sutherland Sharks at an early age.While attending De La Salle in 1993, Ritson was selected to play for the Australian Schoolboys team.