Stengle was taken in by his grandmother, Debra, at the age of four after he and his brother were removed by the state from the care of their parents. He later lived with grandparents Emily and Cecil Betts after Debra died. He spent his teenage years in the north western Adelaide suburb of Ethelton where he completed secondary schooling at Le Fevre High School. Stengle first played football for the localPortland Football Club at under 10s level. There he played in over 100 matches across his junior years. As a teenager he was a member of 's Aboriginal AFL Academy. Stengle played state-league football with Woodville-West Torrens in the South Australian National Football League. He played 10 matches for the reserves team in 2016 and kicked 22 goals, while he kicked 13 in nine matches with the club's Under 18 team that same season. He was a member of the Eagles' reserves Grand Final team in 2016. In 2016 he represented South Australia at the National Under 18 Championships. There he ranked second among all small-forwards for Champion Data ranking points per game. Stengle was also the fourth ranked of all South Australians by the same measure that tournament. He was labelled "quick, creative, innovative and classy" by The Age draft writer Emma Quayle for his performances in the championships. The Advertiser's Andrew Capel said Stengle possessed "brilliant skills, blistering pace and a love of tackling and applying ferocious forward pressure." Stengle recorded a top 10 score in the goalkicking test at the national draft combine in 2016.
AFL career
Richmond (2017–2018)
Stengle was drafted by with the club's first pick and the sixth selection overall in the 2017 AFL rookie draft. Stengle played the early part of the 2017 season with Richmond's reserves side in the VFL. He was a key forward-line player for the side, kicking 13 goals in his first eight matches. He was upgraded to the club's senior list in June 2017. He made his AFL debut two weeks later in Richmond's round 15 win over at the Adelaide Oval where he kicked two goals in the match. He played again the following match but was omitted from the team's round 17 side to play the week after. From there he returned to the club's reserves side, playing with the team through to their finals campaign. There he played in each of their three victories, and in the team's losing grand final against Port Melbourne. Stengle finished the 2017 season having played two matches and kicked two goals at senior level. He also played 19 matches in the reserves and kicked 33 goals, good for the second most at the club and sixth most in the league. In February 2018 Stengle was selected alongside most of the club's younger players to represent Richmond at the Sydney tournament of the AFLX exhibition series. He started the season-proper with the club's reserves side, but was immediately impressive at that level with a 20 disposal and three-goal game in round 1. By round 5 he was named as an emergency for the AFL team, but ultimately went unselected at the top level. In mid-May Stengle turned in a three-goal third quarter during a VFL match with North Melbourne that saw him again named an AFL emergency the next week. He began playing limited midfield minutes in VFL matches from June, adding positional versatility to his predominantly forward-line role. In mid-July Stengle turned in his best performance of the year to-date, kicking a bag of six goals while gathering 24 disposals in Richmond's VFL win over North Melbourne. For that performance he was noted by head coach Damien Hardwick as one of the club's best VFL performers, but went again un-selected for senior football. To that point he had played 13 matches at the lower level for a total of 26 goals, the most for any Richmond player and the sixth most of any player in that league. Two weeks later Stengle suffered a minor ankle injury while playing in a VFL match against. He missed the second half of the match due to the injury as well as one further match while rehabilitating the injury. Stengle finished the home and away VFL season with 33 goals, good for eighth most of any player in the league. He did not add to that tally in the VFL finals series however when Richmond's reserves side were eliminated following consecutive losses to and. He won the club's reserves goal-kicking medal for his 33 goals over 19 matches in the VFL, but failed to earn an AFL match in 2018. In the off-season that followed Stengle became the focus of trade speculation, with an AFL Media report in mid-September claiming that he was delaying acceptance of a two-year contract extension at Richmond while weighing up rival interest from. Less than a week out from the beginning of the trade period, Stengle requested a trade to Adelaide citing a lack of AFL-level opportunity during his time at Richmond.
Adelaide (2019–''present'')
On the penultimate day of the 2018 trade period Stengle was traded to in exchange for a 4th round draft selection in pick 68.
On 17 April 2020, Stengle was reported for drink driving after being stopped by police in Adelaide’s south-western suburbs. He was caught driving an unregistered car and subsequently recorded a blood alcohol reading of 0.125.
