He first attended high school atSt John's Catholic College inDarwin.[2][5] He was the subject to significant media attention from the age of 14, owing to his famous heritage and his special draft status with each ofRichmond,Fremantle andEssendon vying for his commitment, with the first two afforded priority access under thefather–son rule and the third under the AFL's Next Generation Academy rules.[6] Rioli showed the strongest links to Richmond during his early teenage years, regularly visiting the club where his nephewDaniel Rioli was drafted in 2015.[5]
He represented the Northern Territory as a 14-year-old at the 2017 AFL Under-16s Championships where he was a regular goalkicker.[7][8][9] Later that year he made his senior football debut, playing forSt Mary's in theNorthern Territory Football League.[2]
Rioli relocated toMelbourne in early 2018 where he boarded atScotch College.[6][10] He played football for the school that year, as well as once again representing the Territory at the Under 16s Championships.[11][12]
After another summer season with St Mary's, Rioli returned to Melbourne in 2019 where he joined the squad of theOakleigh Chargers, though would not earn a top-flightNAB League match during that his 'underage' year.[6][13][14] Instead, he played NAB League football as part of a representative Northern Territory representative side.[15]
For a third straight season, Rioli played for St Mary's in the 2019/20 summer and into early autumn, ahead of his final year of underage football.[16][17] He played nine games in the season, with his most impressive performance coming with a best-on-ground four goals in a semi-final win, before adding one goal in St Mary's losing grand final showing the following week.[18][19][20][21] That same summer he trained with the AFL squad at Richmond as part of the club's father–son program for which he would be eligible at the coming draft.[22] Rioli intended to play school football with Scotch and with Oakleigh in the NAB League that year, but ultimately each league's season was cancelled along with the AFL Under 18 Championships as a result of public health restrictions imposed in response to theCOVID-19 pandemic.[23][24][25]
In September 2020, Rioli was one of 96 players invited to the AFL Draft Combine.[26][27] Around this time he confirmed years of informal commitment, nominating for selection to Richmond under thefather–son rule.[28][29][30]
Prior to the draft, Rioli was forecast to land with Richmond at pick 47 and 52 byFox Footy andESPN in their respective phantom drafts.[31][32] He was noted for his tackling ability, goal-sense and sprint speed.[6]
He first represented Richmond as part of the club's reserves side, featuring in VFL pre-season matches from February through April when the season officially began.[34][35][36] Rioli impressed over that time, first earning a place as a non-playing emergency in the club's round 5 AFL match againstSt Kilda.[37] Though he went unselected in the final team, he was a stand-out performer at reserves level, kicking two goals and recording 17 disposals in the opening round of the VFL season that same weekend.[38][39] He was an AFL emergency regularly over the month that followed, while continuing to play VFL football as a small forward with occasional stints in the midfield.[40][41] In May, Richmond senior coachDamien Hardwick labelled Rioli close to AFL selection, but said he would require a stronger endurance base before he could be named for a debut.[42] Through the first week of July, he ranked second among midfield-forwards in the VFL with 5.8 tackles per game and was in contention for the league's goal of the year award with a 90-metre sprint goal against the Northern Bullants.[43][44] Following an eight-tackle game against Frankston in early August, Rioli was elevated to senior level and named to make his AFL debut in a round 21 match againstNorth Melbourne.[45][46]
Rioli plays primarily as a defensive small forward and is notable for his ability to apply forward-half pressure and create turnovers among opposition defenders.[47]