When he was 11 years old, Ballo began training with coach Mohamed Diarra in his hometown, eventually earning an invitation from Canterbury Academy, a British private school in Las Palmas, Spain.[4] He enrolled as a full-time student, despite not knowing Spanish or English, and started practicing basketball three times per day.[1] In May 2017, Ballo was named most valuable player (MVP) of the Spain Under-16 Championship after helping Canterbury finish in third place, behind bigger clubs like Barcelona and Real Madrid, and leading the tournament in rebounds.[1][5] In 2018, he averaged 15.1 points, 10.8 rebounds, and 2.3 blocks per game at the Spanish Junior Championship, earning MVP honors.[6]
In 2019, Ballo reclassified from the 2020 recruiting class to the 2019 class and was subsequently rated a four-star recruit by 247Sports and a five-star recruit by Rivals.[10][11] On 23 February 2019, he verbally committed to Gonzaga over offers from Arizona and Baylor, among others.[12][9]
On 28 October 2019, Ballo was ruled an academic redshirt for the 2019–20 season by the National Collegiate Athletic Association.[13] As a freshman, he averaged 2.5 points and 1.5 rebounds per game, earning West Coast Conference (WCC) All-Freshman Team honors. After the season, Ballo transferred to Arizona to play for head coach Tommy Lloyd, who had recruited him to Gonzaga.[14] As a sophomore, Ballo averaged 6.8 points and 4.4 rebounds per game. He averaged 13.9 points and 8.6 rebounds per game as a junior, earning First Team All-Pac-12 as well as Pac-12 Most Improved Player honors.[15]
National team career
Ballo played for Mali at the 2017 FIBA Under-16 African Championship in Vacoas-Phoenix, Mauritius. He averaged 14.4 points and 12.8 rebounds per game, winning the gold medal while making the tournament All-Star Five.[16] Playing for Mali at the 2018 FIBA Under-17 World Cup in Argentina, Ballo averaged 20.6 points and a tournament-high 16.9 rebounds per game and was named to the All-Star Five.[17] On 7 July 2018, he recorded 32 points and a tournament-record 32 rebounds in a 110–108 triple overtime loss to the Dominican Republic.[18] Ballo won a gold medal with Mali at the 2018 FIBA Under-18 African Championship in Bamako, Mali. He averaged 8.5 points and six rebounds per game.[19]
Ballo competed at the 2019 FIBA Under-19 World Cup in Heraklion, Greece, missing the first two games due to visa issues.[20][21] In five games, he averaged 17.6 points, 11.8 rebounds, and 3.8 blocks per game, leading Mali to a silver medal, the best performance by an African team at a global basketball tournament.[21] Ballo was named to the All-Star Five with teammate Siriman Kanouté.[22]
Ballo's mother and father stand 1.96 m (6 ft 5 in) and 2.03 m (6 ft 8 in) respectively. His older brother, Drissa, who stands 2.08 m (6 ft 10 in) and weighs 118 kg (260 lbs), plays professional basketball in France.[1]