Tuhia he haere tonu mō tēnei wāhanga - I te tau 1991, i tohua a Gratton hei tuatoru o te katoa i roto i te OHL Priority Selection e te Kingston Frontenacs. Whai muri i tana tau rookie i te OHL, i whakawhiwhia a Gratton ki te Emms Family Award hei rookie o te tau. I te tau 1993, ko ia te tuatoru o nga whiringa katoa i te NHL Draft
e te kapa Tampa Bay Lightning.